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Porsche M96 vs M97 Engine

November 12, 2021 by porsche Leave a Comment

The Porsche M96 vs M97 engine differences are actually a hotly debated topic. Which cars use the M97 vs M96 and which engines have the fixed IMS bearing are two of the more controversial subjects. We’ll start off by covering the basics on each of the engines, the differences between the two, reliability & problems, and so on. And then we’ll provide our well-researched opinion on the IMS bearing and for what years it was “fixed”.

Both the M96 and M97 are engine families rather than specific engines. The M96 is the earlier version and was produced from 1996 through model year 2007. In model year 2005 the M97 engine started to make an entrance, phasing out the M96 engine. Additionally, both of these engines are used in the 986 & 987 Boxster’s and 996 & 997 Carerra 911’s. The M97 engine was also put into the 987 Cayman starting in model year 2007.

Porsche M96 Engine

The M96 made its introduction in 1996 as a 2.5L flat-six in the Boxster 986. Throughout its heyday from 1996-2005 it powered the Boxster (986 and 987) and Carrera 911 (996 and 997) vehicles. Impressively enough, the M96 came in 5 different engine sizes. The Porsche Boxtser vehicles had three options, a 2.5L, 2.7L, and 3.2L flat-six engine. The 911’s were equipped with larger 3.2L, 3.4L, and 3.6L flat-six options.

The 2.5L engine was only used from 1997-1999. The engine block was poorly designed and Porsche had some quality control issues in the factory that were leading to cracked cylinder liners. The 2.7L entered in 1999 as a replacement for the 2.5L. The 3.2L option was offered along side these smaller engines for “S” series cars.

The M96 engine receives a lot of criticism due to IMS bearing (intermediate shaft) failures, rear main seal leaks, and cylinder cracking. We’ll discuss these in more depth below.

Porsche M97 Engine

Similar to the M96 engine, the M97 is a 24-valvve water-cooler flat-6. However, while the engine was built off of the same platform as the M96 it features a number of differences that we’ll cover below. The M97 was produced in 2.7L, 3.4L, 3.6L, 3.8L, and 4.0L engine sizes.

Starting in mid-2005 the 997 Carerra S began receiving the M97 engine. Until 2008 the base model 911 Carerra’s used the M96 engine which was eventually phased out in 2009 by the direct-injected MA1 engine. Both the 987 base Boxster and S series had the M96 engine in it until 2007 when they received the newer M97 engine.

The IMS bearing was purportedly fixed for the M97 engine. While failure can still happen and some people still have concerns with the bearing, the failure rate is lower than on the earlier M96 engines. However, M97 IMS bearing failure is a lot more costly as it requires the majority of the engine to be taken apart to get to it.

M96 vs M97 Engine Differences

Although these two engines are very similar in nature there are some important differentiations. We’ll cover the big differences here and then provide some thoughts on the IMS bearings between the two since that is a debated topic.

Increased Displacement

The first and most noticeable difference is that the M97 is a larger engine. While the Boxsters with the M97 still received 2.7L that was used in the base model, the Boxster S 3.2L was increased to a 3.4L, increasing power from 276hp to 291hp. The 2.7L received a small 5hp increase. When the 987 Cayman was released in 2007 it followed the same 2.7L base model and 3.4L S model structure.

For the 911 Carerra, the M97 was also still produced in a 3.6L size, similar to the M96. S models however did receive a larger 3.8L engine. And a 4.0L engine was produced specifically for the GT3 RS 4.0.

Displacement was increased by boring out the cylinders and fitting in larger pistons. Overall, the S models received larger engines while the base models kept the same sizes as the M96 predecessor with only minor power increases.

Adjusted Timing

Aside from the larger displacement, the timing was adjusted to create a smoother torque curve and to handle the power increases caused by the larger engine sizes. However, the intake and exhaust valves remain very similar to the M96 in terns of lift and sizing.

Jet Pump to Mechanical Pump

The brake booster vacuum pump for the M96 was a “suction jet pump”. The details of how jet pumps work are rather technical, so you can read about it here if you’re intrigued. The M97 received an upgraded pump and switched from the suction jet design to a mechanical pump. Avoiding the technical differences, the mechanical pump provides more consistent vacuum supply and therefore a more consistent braking experience, especially when at altitude or when driving aggressively such as on a track.

Electronic Oil Level Sensor

The only way to check oil levels on the M96 engine is by pulling out the dipstick. It had no electronic oil monitoring. The M97 added electronic oil level monitoring so that you could see at all time where oil levels were at, the temperature of the oil, and oil usage. While not a major change oil level monitoring is a good feature to have to prevent serious engine damage from running low on oil. It is also helpful for detecting leaks.

M96/M97 IMS Bearing Upgrade

This topic is where the debate begins. We’ve done a lot of research on IMS bearings and will provide what we believe to be an accurate assessment.

From 1997 until early 2005 the M96 engine used two different IMS bearing designs: the dual-row 5204 bearing and the single-row 6204 bearing. The 5204 bearing was used until early 2000 when it was replaced with the 6204 bearing. The bearing seals on the 5204 bearing deteriorated over time leading to failure. Failure was most commonly associated with age of the bearing and not necessarily mileage on the engine.

Porsche changed the design in early 2000 due to failures and problems with the 5204 bearing. However, the single-row 6204 design is actually considered the least reliable of them all. So, in early 2005 a larger single-row 6305 bearing was introduced. It was bigger and stronger but still not bulletproof, albeit it is considered the strongest of the three.

So, Porsche fixed the majority of the IMS bearing issues in early 2005, although 2005+ IMS bearings are still susceptible to failure. But the number of cases of IMS bearing failures with the 6305 is a lot less than the predecessors.

So, which Porsche engines have the “fixed” IMS bearing?

Since the 6305 bearing wasn’t fitted until some time in the earlier part of 2005, there are some very early M97 engines that still have the bad 6204 bearings. The bearings were also upgraded for the M96 engine at the same time.

So, there are both M96 and M97 engines with old and new bearings on them. Anything with a build date of mid-2005 or later should have the better IMS bearing whereas anything before that will have the worst of the three. It isn’t clear exactly when the switch took place so it is difficult to say whether engines with early 2005 build dates have the new or old bearings.

The downside to the M97 engine’s IMS bearing is that it requires a complete teardown to access it, whereas you only need to remove the flywheel on the M96 engine to access it. While M97 IMS bearing failure is a lot less likely, it is a lot more costly to fix if it does break.

Porsche M96 vs M97 Reliability

The most common M96 engine problems are IMS bearing failure, rear main seal oil leaks, cracked cylinders, and cylinder scoring. Unfortunately, the problems that are common with this engine are on the more expensive side to fix. IMS bearing and rear main seal issues are most common in old cars that haven’t been driven frequently and spent a long time sitting. So while a nice super low mileage M96 might sound tempting, the RMS and IMS are probably ticking time bombs. Fortunately, the IMS bearing can be preventively fixed. We’d give the M96 an average grade for reliability without the IMS fix, and slightly above average when it is fixed.

The vast majority of the M97 engines have the improved IMS bearing which gives this engine a leg up in reliability over the M96. Common M97 engine problems are cylinder scoring, cam solenoid failure, and coolant pipe failure. Most of the reliability issues with the M97 stem from the engine overheating and causing cooling system failures. When properly maintained and cared for, the M97 engine offers solid reliability.

Overall, the M97 is considered to be more reliable than the M96, predominantly since there are a lot less M97’s out there with the old IMS bearings. A 2005+ M96 will be pretty comparable to the M97 in terms of reliability since both with have the stronger and improved bearing.

Porsche’s are unfortunately very expensive to fix. And in terms of reliability costs, the M96 wins since it is a bit cheaper and easier to service compared to the M97. Overall, these are both great engines. But proper maintenance and care is vital for them to remain reliable.

The 6 Most Common Porsche 955/957/958 Cayenne Engine Problems

November 1, 2021 by porsche Leave a Comment

Porsche’s Cayenne made its introduction back in 2002 and is still being produced today. There have been three generations since its introduction. The first-generation, often referred to as the 9PA Cayenne or the Porsche 955, was built on the Volkswagen Group PL71 platform and ran from 2003 – 2010. The second-generation, often referred to as the 92A Cayenne, was built on the Volkswagen Group PL72 platform and ran from 2011 – 2018. And lastly, the third-generation, often referred to as the 9YO Cayenne, was built on the Volkswagen Group MLB Evo platform and started production in 2018 and is still being produced today.

An interesting fact about the Porsche Cayenne, is that it holds a Guinness World Record for the heaviest aircraft, 265-ton Air France Airbus A380, pulled by a production car. As many can imagine, Porsche produced many trims of the Porsche Cayenne: Cayenne, Cayenne S, Cayenne S Hybrid, Cayenne S E-Hybrid, Cayenne GTS, Cayenne Turbo, Cayenne Turbo S, Cayenne Turbo S E-Hybrid, Cayenne Turbo GT, Cayenne Diesel, and Cayenne S Diesel. With all of these trims, there are also many different engines.

First Generation Porsche 955/957 Cayenne Engines

The first generation came with 11 different engines but we will try to compact the information as much as possible. The Base Cayenne came with a 3.2L VR6 engine that put down anywhere from 247hp – 286hp & 229lb-ft – 284lb-ft of torque. The S came with a 4.5L V8 engine that put down 335hp – 399hp & 310lb-ft – 369lb-ft. The GTS came with a 4.8L V8 that put down 399hp and 369lb-ft of torque. The Turbo came with a twin-turbo 4.8L V8 & a twin-turbo 4.5L V8 that put down anywhere from 444hp – 493hp & 457lb-ft – 516lb-ft of torque. The Turbo S featured a twin-turbo 4.5L V8 that put down anywhere from 513hp – 542hp & 531lb-ft – 553lb-ft of torque. Lastly, the diesel featured a 3.0L V6 engine that put down 237hp & 406lb-ft of torque.

Second Generation Porsche 958 Cayenne Engines

The second generation came with even more engines coming in at 16. The Base Cayenne came with a 3.6L VR6 engine that put down anywhere from 296hp & 295 lb-ft of torque. The Cayenne S came with a 4.8L V8 NA engine that put out 395hp and 369lb-ft of torque and a twin-turbo 3.6L V6 that put down 414hp & 369lb-ft. The GTS featured a NA 4.8L V8 that put down 414hp & 380lb-ft and a twin-turbo 3.6L V6 that put down 434hp & 443lb-ft of torque. The Turbo and Turbo S featured a twin-turbo 4.8L V8 that put down anywhere from 493hp – 562hp & 516lb-ft – 590lb-ft of torque. The Diesel had a single-turbo 3.0L V6 that put down anywhere from 237hp – 258hp & 406lb-ft – 428lb-ft of torque. Lastly, the Cayenne S Diesel featured a twin-turbo 4.1L V8 that put down 380hp & 627lb-ft of torque.

Third Generation Porsche 9YA or P0536 Cayenne Engines

And finally, the third generation had fewer engines. The base Cayenne features a single-turbo 3.0L V6 that puts down 335hp & 332lb-ft of torque. The Cayenne S featured a twin-turbo 2.9L V6 that puts down 434hp & 406lb-ft of torque. The GTS & Turbo features a twin-turbo 4.0L V8 that puts down anywhere from 434hp – 454hp & 406lb-ft – 457lb-ft of torque. The Turbo S E-Hybrid features a twin-turbo 4.0L V8 PHEV that puts down anywhere from 671hp – 690hp & 642lb-ft – 664lb-ft of torque. Lastly, the all-new Cayenne Turbo GT features a twin-turbo 4.0L V8 that puts down 631hp & 626lb-ft of torque.

Common Porsche Cayenne Engine Problems

Before getting into the Porshe Cayenne engine problems, we want to preface that since there are a lot of engines, we will try to differentiate which generation has the most common problem listed below. Also, for the replacement parts linked below, please make sure they fit your vehicle if you have to order them. If not, let us know in the comments and we will assist in any way possible.

Ignition coil or spark plug failure
Faulty fuel pump
Thermostat failure
Plastic coolant lines – 2011-2019 V8
Transfer case failure
Cam adjuster bolt failure – 2010 – 2012 V8

1. Ignition Coil or Spark Plug Failure

Premature ignition coil or spark plug failure is common in many Porsche engines. Therefore, this problems is not solely associated to a specific Cayenne. Spark plugs need high voltage electricity to be able to create a “spark” in the combustion chamber initiating engine combustion. Ignition coils receives lower voltage electricity from the battery and transforms it into the higher voltage spark plugs need.

There are two main reasons why ignition coils and spark plugs fail: normal wear and tear or modifying an engine. Modifying an engine and creating more power will put more heat and stress on the coils and plugs, which often will cause a couple to fail instantly. When they do fail, there will be misfires in the specific cylinder with the faulty coil or plug. Most ignition coils and spark plugs SHOULD last 60,000 miles or more. However, we’ve seen some last 5,000 miles and some last 80,000 miles.

Symptoms of Ignition Coil or Spark Plug Failure:

CEL/MIL illuminating
Engine misfires with fault codes P0300 – P0308
Poor engine performance
Issues starting the engine
Engine surging or stalling

Ignition Coil and Spark Plug Replacement Options:

When an ignition coil or spark plug does happen to go out, we advise replacing all of them while you’re at it to avoid future misfire headaches down the road. Ignition coil and spark plug replacement is not the toughest DIY if you have the proper tools and know the location of the coils. A mechanic or local dealer would likely charge anywhere from $450 – $600 to replace both the coils and spark plugs.

Ignition Coil Pack Replacement: https://amzn.to/3mwwEuH
DIY Difficulty: Easy

2. Faulty Fuel Pump

When we mention fuel pumps, we’re referencing both older low pressure fuel pumps and newer high-pressure fuel pumps, or HPFP. Older 955 Cayenne’s have two pumps low pressure (in-tank) fuel pumps, while newer 958/9YA Cayenne’s have a HPFP (or high-pressure fuel pump) because of direct injection. Low pressure fuel pumps are located in the fuel tank, while the HPFP is typically mounted on the left side cam. A fuel pump pumps fuel from the fuel tank and sends it to the engine. A HPFP on newer Cayenne’s pumps high-pressure fuel into the direct injection system.

The low pressure fuel pumps tend to fail because the pump itself tends to overheat and shut off. The HPFP tends to fail because something inside the pump comes apart or the valve on top of the pump can fail. When either fail, expect engine sputters, misfires, and poor engine performance. Typically, fuel pumps fail at least once in a vehicle’s lifecycle.

Symptoms of Fuel Pump Failure:

Whining noise coming from the fuel tank
Difficulty starting the engine
Engine surges, sputters, or stalls
Engine dying
Decreased fuel economy
Poor engine performance while accelerating

Fuel Pump Replacement Options:

When a fuel pump, whether it be the low pressures or high pressure, goes bad, 9/10 times they will have to be replaced. There are times when you can just replace a gasket on the HPFP if it is leaking, but this is not too common. If a low pressure fuel pump happens to go out, we highly suggest replacing both and the associated filter. Replacing either the HPFP or the low pressure fuel pumps is not the easiest DIY unless you know where they are located. A mechanic will likely charge around $1,200 depending on which pumps are being replaced.

DIY Difficulty: Difficult

3. Thermostat Failure

Thermostat failure, like ignition coils and spark plugs, is common in many other Porsche engines. A thermostat controls the amount of coolant that is recirculated back into the engine and how much coolant is cooled by the radiator before recirculating. There are a few reasons why a thermostat can fail: being stuck ope, being stuck closed, or gasket failure. When it does fail, the engine temps will be high, which will lead to the engine overheating.

Symptoms of Thermostat Failure:

High engine temps
Low coolant indicator illuminating
Engine overheating
Sporadic temperature readings on the dash
Improper coolant flow

Thermostat Replacement Options:

Typically when a thermostat fails, we would advise replacing the water pump as well because typically these go out around the same time. Also, because they are right next to each other. We classified the DIY as difficult, because both the thermostat and water pump are rather hard to get to. However, there are many video tutorials online if you are trying to save some labor costs. A mechanic or dealer will more than likely charge $1,000 to replace only the thermostat.

DIY Difficulty: Difficult

4. Plastic Coolant Lines or Epoxy Failure

For some reason, Porsche decided to put plastic coolant pipes in Cayenne engines. Specifically, there is a lawsuit against Porsche for all 2011 – 2019 V8 958 Cayenne’s. Coolant pipes moves coolant from the radiator to the hottest part of the engine and back to the radiator to cool off before going through the same process over and over again.

The coolant pipes are located below the intake manifold, which is not the coldest place for plastic components to be. The pipes and epoxy tend to fail over time because of all the heat they endure. When they do fail, whether it be the epoxy or the pipes, steam will more than likely start coming out of the engine and the engine could die.

Symptoms of Plastic Coolant Lines or Epoxy Failure:

Low coolant indicator illuminating
Steam coming from the engine
Difficulty starting the engine
Engine overheating
Loss of engine power
Engine dying

Plastic Coolant Lines Replacement Options:

When the epoxy degrades over time or the plastic coolant pipes start to wear, the only thing to do is to replace them. You can try adding more epoxy on the ends, but we highly don’t recommend doing so. When replacing, we highly advise using aluminum pipes to avoid the plastic ones from going out again. The pipes are a little difficult to get to, but there are plenty of tutorials online explaining the DIY, so it isn’t too hard. Since Porsche, as of writing this, doesn’t cover this repair, you will likely have a dealership charge $3,500 to replace the plastic pipes with alluminum coolant pipes.

DIY Difficulty: Intermediate

5. Transfer Case Failure

The most common model year for transfer case failure is 2012, but that certainly is not the only Cayenne that experiences transfer case failure. This is typically found in Cayenne’s with 4WD. A transfer case attaches to the transmission and connects the front a rear drive axles of a 4WD vehicle and it routes torque from the transmission to the axles.

These prematurely fail due to normal wear and tear. When they fail, it causes a miscalculation from the intended wheel speed versus the actual wheel speed. This was such a big issue that Porsche extended the warranty period for the factory transfer cases’ because after many attempts to remedy the faulty transfer cases’, they are still an issue. Typically, transfer cases should not fail at all on a vehicle’s lifecycle.

Symptoms of Transfer Case Failure:

Sporadic acceleration
Vibrations while accelerating
Engine jerking
Difficulty switching gears
Grinding, howling, or humming noise coming from the engine
4WD not engaging

Transfer Case Replacement Options:

When a transfer case wears, the only option is to replace it. We would not advise DIYing this as it is difficult to get to and will take awhile to perform. Unfortunately, Porsche is not covering the cost of transfer case replacement after the extended warranty expires. Customers have been seen to pay an absurd amount to replace the transfer case of up to $5,500 mainly due to the cost of the replacement part.

DIY Difficulty: Difficult

6. Camshaft Actuator Failure

Camshaft actuator failure is common in 2010 – 2012 958 Cayenne’s with a V8. However, the problem is not the camshaft actuator itself, it is the bolts securing the timing chain sprockets. A camshaft actuator is located at the end of the camshaft and it controls the speed of the opening or closing of the poppet valves, which enables engine timing to be more precise. The camshaft actuator bolts hold the camshaft actuator in place.

When the bolts for the camshaft actuator fall off, engine timing is thrown off and the engine will run very roughly. The bolts should not break at all in any engine nowadays. This was such a problem that Porsche actually issued a recall on 2010 – 2012 Cayenne’s to correct the bolts.

Symptoms of Camshaft Actuator Failure:

Poor engine performance
Engine stalls
Engine timing off
CEL or MIL illuminating with a P0340 or more camshaft related fault codes
Rough idle
Decreased fuel efficiency

Camshaft Actuator Replacement Options:

If you happen to own a 958 Cayenne and haven’t had this issue yet, we highly advise replacing the associated bolts to avoid the adjuster failing. As you can imagine, this is also not an easy DIY as you have to take many components out of the engine to get to the bolts. If you have a 2010 – 2012 Cayenne, make sure to check if these have been changed and if not, it should be covered under Porsche. If you don’t have a 2010 – 2012, unfortunately, you will more than likely have to pony up anywhere from $2,000 – $5,000 depending on if there is major engine damage.

DIY Difficulty: Difficult

Porsche Cayenne Reliability

Overall, we aren’t going to sugarcoat it, Porsche Cayenne’s reliability is below average compared to its competitors. However, some model years, specifically 2014 & 2016-2017, are tainting this overall rating. The good news is the 2021 Porsche Cayenne has a J.D. Power reliability rating of 81 out of 100. A good rule of thumb would be to avoid the early model years of all the generations to avoid the initial hiccups. With all of that said, we have seen many Porsche Cayenne’s last well over 200,000 miles with proper maintenance.

If you want to read up on more Porsche content, here’s our write-up on “The 4 Most Common Porsche M97 Engine Problems”.

Porsche 944 Performance Mods & Upgrades

October 27, 2021 by porsche 1 Comment

The Porsche 944 was produced from 1982 until 1991. Unlike traditional Porsche’s, the 944 is a front-engine design. For model year 1992 the 944 received numerous updates and a new design which prompted Porsche to rebrand the car the Porsche 968. The 944 and 968 share about 20% of the same parts.

The 944 came in three different trims: the base model 944, the 944 Turbo, and the 944 S. The 944S model received an update in 1989, dubbed the 944 S2. Additionally, cabriolet versions were produced for the S2 and Turbo.

Throughout it’s 9 year production history, four different engines were used. Three were naturally aspirated and came in 2.5L, 2.7L, and 3.0L sizes. The 2.5L I4 was the base model engine producing 143-161hp and was also used in the first 944 S models from 1987-1989 which produced 187hp due to a new 4-valve design. The 2.7L is a rare engine used only in 1989 base models. The 944 S models from 1989 onwards, dubbed the 944 S2, received a larger 3.0L engine which output 208hp. And lastly, the 944 Turbo models all received a 2.5L I4 equipped with a turbocharger, producing 217-247hp.

This guide is going to cover the best performance mods for the Porsche 944. It will be more geared towards the base 2.5L engines. While power gains will vary slightly for NA models, the recommended modifications and performance upgrades are the same for the 2.7 and 3.0 models as well.

Porsche 944 NA Mods

Headers
Upgraded camshaft
High-flow cat or cat-delete
MAF conversion
ECU tune
Throttle response cam

Ultimately, mods don’t do too much for the 944 NA 2.5 which is why we only recommend a few of them. A bit later down we’re going to cover some more advanced mods at a high level that can get your NA 944 above the 200hp mark. But note these are very advanced and expensive mods which is why we aren’t going to recommend them here. However, this wouldn’t be a complete guide without giving you a flavor of other possible 2.5L NA mods.

Rather than dumping significant amounts of money into power-adding mods, most enthusiasts recommend spending the money on suspension, handling, and weight reduction mods.

1) 944 NA Header Upgrade

Headers are the first component of the exhaust system and also tend to be one of the most restrictive components. On the earlier year 8-vavle 2.5’s, headers don’t provide a ton of performance value as their stock headers aren’t quite as restrictive considering less valves and lower power. On the 1987-1989 16-valve engines the headers gains are more meaningful.

Headers increase power by reducing backpressure in the exhaust system. Backpressure causes exhaust gases to seep back into the combustion chamber and therefore increase air temps and decrease the amount of oxygen in the chamber. The second benefit is through weight reduction. A set of aftermarket headers will shave off about 10lbs. of weight.

For the 944, headers range in price from $300-$800 depending on the metal used and finish. Most of the brands offered will provide the same performance benefit but lower quality metals can rust and crack so we recommend a good 304 stainless steel option.

Header Upgrade Benefits

~2whp for 8v 944’s and similar torque gains
~8whp for 16v 944’s and similar torque gains
Decreased backpressure
Slightly louder exhaust note
Better throttle response

2) Porsche 944 Camshaft Upgrades

Camshaft upgrades aren’t necessarily the most beginner friendly mod but do offer some decent gains for the 944. The gains here are realized from going with a more aggressive cam grind. Cams with more aggressive profiles have longer duration and higher lifts which open the valves further and keep them open longer.

Cam selection is a bit more of an advanced topic so we’re going to stay away from covering it in this article and instead focus on the performance gains an upgraded cam can provide on the Porsche 944. However, gains ultimately depend on the cam you choose and other mods present on the car. On the downside of cam upgrades is the higher RPM’s it causes result in added heat and engine stress

944 NA Camshaft Upgrade Benefits

~5-10whp gains (not necessarily peak)
Improved low end torque
Better throttle response

3) High-Flow Cat or Cat Delete

Between the headers and the cat-back portion of the exhaust sits the catalytic converter, or cat. The cat is generally the most restrictive exhaust component and therefore creates the most backpressure. Similar to headers, upgrading the stock cat reduces backpressure in the exhaust system and therefore improves power.

You have two options: replace the stock cat with a high-flow cat, or completely delete the cat itself. Deleting the cat is technically illegal but reduces backpressure the most and therefore offers better power gains. Keeping the cat keeps the car legal and is less harmful to the environment but offers less gains since it is still somewhat restrictive. However, due to the age of these cars you might be exempt from emissions testing in the first place depending on where you live.

A high flow cat will provide about 5whp gains whereas completely deleting it can provide closer to 10whp gains. One other consideration is that deleting the cat and using a “test pipe” is a lot cheaper since it doesn’t have the catalytic converter which uses exotic metals inside.

The remaining cat-back portion of the exhaust can be upgraded as well but provides pretty negligible power gains which is why we mostly recommend the header and cat pipe mods.

Porsche 944 High Flow Cat & Test Pipe Mod Benefits

~5whp for high-flow cats
~10whp for cat-delete aka test pipes
Louder exhaust note (only noticeable if cat is deleted)
Reduced exhaust backpressure
Lower exhaust gas temps

4) Porsche 944 MAF Conversion

Along with a cat-delete an MAF conversion is probably among the best Porsche 944 mods on this list. The stock air system uses an air-flow-meter (AFM) which is highly restrictive. This mod deletes the AFM and converts the car to a mass-air-flow sensor driven air intake system. In addition to significantly improving airflow it also allows for more precise air-to-fuel ratios creating more power and smoother power curve.

The one downside to the 944 MAF mod is that you need an 1985/2 or later DME. The 24 pin DME chip needs to be converted to a 28-pin and unfortunately the 1985/1 and earlier DME’s have the chip soldered into place whereas the later years are plug and play. Modification of the DME is required so that the DME understands the conversion from AFM to MAF.

Here is an example of a kit from one of the best on the market, Lindsey Racing MAF Kit.

MAF Conversion Benefits

5%-10% power gains (approx. 10-15whp gains)
Increased air flow, less restriction
More linear power delivery
AFRs adjust to improve power gains from other mods

5) Porsche 944 DME Tune / Chip

The stock DME isn’t optimally tuned, especially when the 944 is modded. One of the best way to get a healthier engine and increase power is through tuning the DME. There are a few options here. First, you can get a dyno tune done by someone who can tune the stock DME. Second, you can get a standalone DME. Or third, you can “chip” the DME.

Finding a tuner who can play with the stock DME is difficult. Standalone is an option but they are $800+ and likely still requires some custom tuning to it. Therefore, our favorite option is chipping it considering it costs about $250. Getting a standalone is a great mod but we’re not sure it’s worth the cost unless you need extra customizability and all the additional benefits they offer.

For chipping, similar to the last mod you need an ’85/2 or later DME since it requires swapping out the chip inside of it. On the 2.5 NA 8v the Lindsey Racing chip is good for 7whp peak gains with maximum gains of about 12whp in the upper rev range.

944 NA Chipping Benefits

7whp peak gains
12whp max gains
Smoother power curve
Overall healthier engine

6) 944 Throttle Response Cam

We’ll keep this one brief since the mod is super simple and very inexpensive, albeit it does not provide any power gains. The throttle on the 944 is opened via a cam and wire. The stock cam comes in a funky shape with an outward arm that causes the cam to turn slower for the first 1/3 of the throttle. This means that the throttle opens more slowly when your foot is initially pressing down on the gas pedal.

This decreases acceleration and throttle response. For $30 you can get a round throttle response cam that opens 1:1 with your foot on the gas pedal. While this doesn’t increase power it has a huge impact on throttle response. Better throttle response equals faster acceleration. Overall, it’s one of the best mods at making your car feel a little more alive and a bit faster off the line. Installing the part takes about 5 minutes, and at $30, why not?

Should I just buy an S2 or 944 Turbo?

Most people on the forums will tell you to buy a Turbo or a 3.0L S2 engine and swap it into your 944, or just buy the whole car. The base model 944’s with the 2.5L can get to around 230whp but this requires about $7,500 in mods which is about what it costs to buy a 944 Turbo or S2 in the first place. With that being said, this guide is going to cover some basic bolt-on mods to make some modest power improvements.

If you are chasing 200+hp on a base 944 then I would also agree with selling your car and buying a Turbo or S2. Doing so on the NA 2.5L will require cam, lifter, piston, valve spring, porting, etc. etc. which is quite a bit of work and not cheap. Since these are more advanced engine mods we aren’t going to cover them in this guide but will lay them out in a section below.

Base 944’s today are going anywhere from $5k-$10k. S2 models are in the $10k-$20k range and turbo models go anywhere from the upper teens to $30k+. If you just want a 944 for fun and don’t care about performance then go for it. But if performance is a factor for you and you plan on adding mods, an S2 944 is going to be cheaper than getting a base 2.5 NA and modding it to the power levels of the S2. And same goes for getting an S2 vs. a Turbo.

Porsche 944 Advanced Mods for 200hp+

If money isn’t a factor and you want to max out the 944 2.5L NA, then here is a list of all the things you’re going to need to do. Everything on this list is going to run you about $10k-$15k and will get you around the 225-230whp mark. You will be putting out pretty close to 944 Turbo levels, but to really surpass those you’re then going to need to add a turbo which isn’t really ever done.

Turbo kits aren’t a thing unfortunately so you need to build it all in house. And you’re not going to find many people who have tried. The ones that have tried have spent more money doing it than it would cost to buy a 944 turbo itself. Here is some helpful information for the curious, though.

Anyways, here is our list of things you’ll need to push the 230whp mark on an NA Porsche 944.

Built Motor
- Pistons, rings, wrist pins, valves, springs, lifters, camshaft, crankshaft, etc.
Block Upgrades
- Bored and strengthened, main saddle upgrade, ported combustion chamber, main caps strengthened
Cylinder head strengthened
Lightweight flywheel
Stroker kit
Headers and high-flow cat
Tune / engine management

2.5L Porsche 944 NA Mods Summary

The 6 mods listed in this guide will give you a nice 30-40whp gains. However, getting there will cost you somewhere around $2,000 to $4,000 depending on the products you choose. This isn’t necessarily expensive but it’s also not cheap when considering the initial cost of a 944 today and the cost relative to just buying an S2 or Turbo. Also, for what it’s worth, a lot of people will argue and claim that these mods we listed will get you more like 10whp.

For someone just looking for a bit more power out of the 2.5L, headers and a cat delete, an ECU chip, MAF conversion, and throttle response cam are great options. Upgrading the cam itself is a bit more of an advanced topic and can have an impact on lifters, springs, etc.

If you want to spend $5k+ you can get to 200whp with a few additional mods. And if you want to then spend another $10k+ you can get to 230whp or so which is considered pretty much maxed out for the 2.5 NA 944. Anything beyond that will require a turbo as well but adding one is quite challenging and not really worth the cost.

With all this being said, adding a few of the less expensive mods like a chip and cat delete and spending the rest of your money on weight reduction and handling mods is probably the best option. Or just save up a little bit more money and buy an S2 or Turbo instead if power matters to you.

Overall these are fun cars but the power potential is limited and doing anything about it is expensive. What has your experience been like with modding the Porsche 944?

The 4 Most Common Porsche M97 Engine Problems

June 29, 2021 by porsche Leave a Comment

The Porsche M97 engine was the successor to the M96 engine which rolled out for the Boxster’s, Cayman’s, and 911’s from 2005 – 2011. The engine was produced in four different sizes: 2.7L, 3.4L, 3.6L, and 3.8L and was used in Porsche’s from base model Boxsters to the top of the line GT2 RS. The M97 engine is a water-cooled, 24-valve boxer flat-six.

The M97 was retired in most vehicles in 2008, although it lasted in high-performance models until 2011. It was replaced with the direct-injected MA1 / 9A1 engine.

You can check out the most common problems with the M96 engine here.

Porsche’s using the M97 engine

Porsche 987 Boxster:

2007-2008 Boxster Base – 2.7L M97.20 (242hp)
2007-2008 Boxster S – 3.4L M97.21 (291hp)
2008 Boxster S “RS Spyder” – 3.4L M97.22 (299hp)

Porsche 987 Cayman:

2007-2008 Cayman Base – 2.7L M97.20 (242hp)
2006-2008 Cayman S – 3.4L M97.21 (291hp)
2008 Cayman S Sport – 3.4L M97.22 (299hp)

Porsche 997 Carrera 911 S:

2005-2008 911 Coupe S – 3.8L M97.01 (350hp)
2007-2011 911 GT3/RS/RS 4.0
- 3.6L M97.76 (409hp)
- 3.8L M97.77 (449hp)
- 4.0L M97.74 (493hp)
2008-2011 911 GT2/RS – 3.6L M97.70s (523hp)
2007-2009 911 Turbo – 3.6L M97.70 (473hp)

Porsche M96 vs. M97 Engine

The M97 engine is the successor to the M96, and as such was built off-of the M96 engine. Porsche made a handful of material improvements in the M97, but overall, the engines remain very similar in nature and are often subject to a lot of debate on which is better.

Increased Displacement

The top-end M97 engine displacement was upgraded to 3.8L from 3.6L for the 997 Carrera S models. The baseline 997 Carrera’s retained the same 3.6L M96 engine. Porsche increased the displacement by increasing the cylinder bore sizes and fitting them with larger pistons. The increase displacement brought the power up from approximately 316hp to 350hp in S models, and 376hp in S models with the powerkit upgrade.

M97 IMS Bearing Upgrade

Second, the IMS bearing was improved to be bigger and more sturdy. This has eliminated the majority of IMS failure cases although the problem is still hotly debated and discussed on the forums. The IMS bearing received an upgrade in the M96 in 2005 as well as the engine was continued on into the base model 987 and 997 Porsche’s.

Other Upgrades

The two largest improvements were the increased displacement and upgraded IMS bearing. In addition to these changes the M97 also received a timing adjustment allowing for a smoother torque curve and higher power output. The jet pump powering the brake booster vacuum was replaced with a mechanical vacuum pump. Lastly, the M97 received an electronic oil level management system that allowed the car to monitor oil levels while running instead of manually only while the engine is off.

Porsche M97 Engine Problems

IMS Bearing Failure (Not actually common)
Cylinder Scoring
Cam Solenoid Failure
Coolant Pipe Failure

1. M97 IMS Bearing Failure (Not actually common)

You can read all about IMS bearing failures in our recent post on “The 4 Most Common Porsche Boxster 986 Problems”, but we figured we’d briefly touch on it for the M97 engine since it is so frequently brought up. As mentioned above, one of the primary reasons for the M97 engine was to get rid of the IMS problem that blew up with the M96 engine.

Even with the M96 engine, the failure rate of the IMS bearing is roughly estimated to be 5% or less. The reason that this has blown up to be a “common” problem is due to the cost to replace the engine of a Porsche. This is even more so in the case of the M97 engine. The IMS bearing rarely ever fails on the M97 engine – even on cars that aren’t well taken care of; however, it is still possible for it to happen. Due to the large amount of publicity and high repair costs of IMS bearing failures, we have included it, but it is not a common problem. As with the M96 engine, if you want to highly reduce the chances of a bearing failure, drive your Porsche regularly and replace your oil regularly.

M97 IMS Bearing Failure Symptoms

Oil contains metal shavings
Engine makes a knocking noise
Leaking oil from back of engine

There aren’t any significant signs that automatically tell you the IMS bearing will fail, but if you notice any of these symptoms take your car to a mechanic. Catching it early can help you save some of your engine instead of having a full rebuild. IMS bearings also fail at any mileage, some reported as early as 3,000 miles. As stated before, though, this is primarily a problem for the M96 engine and not with the M97 engine.

Porsche IMS Bearing Replacement Options

There isn’t any cheap solution to fixing this problem. Best case scenario, you are replacing a portion of the engine. Worst case scenario, you are doing a full rebuild or getting a new engine. Neither of these options are appealing, so just take proper care of your car. The IMS bearing rarely fails on M97 engines, especially those that get regular oil changes and are regularly driven. Your Porsche is not meant to sit in the garage, so get out and drive it – it’ll be fun and just may save the engine.

2. M97 Cylinder Scoring

Cylinder scoring is the most common issue that results in engine failure for 997’s and the M97 engine. Cylinder scoring is typically the result of a piston striking the side of the cylinder causing grooves in the cylinder wall. This is often caused by poor lubrication.

If you continually make short trips (city driving), there is a greater chance of this occurring as condensation will mix with oil. If your engine never reaches operating temperature the water molecules won’t be burn off.

Cylinder Scoring Symptoms

One exhaust pipe is coated in black soot
The engine making a knocking noise that resembles a hydraulic lift
Increase in oil consumption

Porsche M97 Cylinder Scoring Repair Options

Bore scoring always results in complete engine disassembly, so it is not a cheap problem to fix. There are ways to address the problem for a cheaper cost, but they do not fix the problem. You can have a metal sheet fitted to the problematic cylinder, but this does not fix the bore scoring. It, mostly, temporarily, addresses the problem.

If you are looking for a more permanent fix, LN Engineering will add “nickies” and replace most of the engine parts such as the pistons and rings. This will be a much more expensive process, but it will fix the cylinder scoring and prevent it from happening again.

3. Porsche M97 Coolant Pipe Failure

This primarily occurs for the 997.1 Turbo engine as Porsche fit it with plastic water pipe seals. Over time the seal will degrade and lead to leaking coolant out of the back on a rear-engine car. It starts slow, but eventually can become a big problem as an over-heated engine can cause a lot of problems for Porsche owners.

Coolant Pipe Failure Symptoms

Leaking coolant
High engine temps

Porsche Coolant Pipe Replacement Options

As with most repairs for Porsche’s, this is not a cheap fix. The best option is to upgrade the plastic outlets to metal ones which requires the engine to be removed. You can either upgrade this before any problems occur, or wait until you notice coolant leaking. There is risk in waiting because if you don’t catch the coolant leaking early, you gamble with blowing your water pump or cracking your cylinders which can be more costly than addressing the issue before it becomes a problem.

4. Heavy Clutch – M97 Engine 997.1

This is more so a warning than a large problem with a lot of 997.1 Turbo engines. There are many people out there who report their clutch pedal to be significantly heavier than any other manual car they’ve driven. It can also get worse with added friction from regular wear and tear.

This is primarily an issue for people with knee issues. Some 997.1 owners report only being able to drive for 30 minutes at a time due to the physical stress from operating the clutch. If this pertains to you, then you may want to look at replacing the clutch power spring and/or the slave cylinder.

Porsche Heavy Clutch Symptoms

The clutch is heavy
Difficult to press clutch pedal in
Knee pain after long drives

Heavy Clutch Replacement Options

The clutch isn’t going to weigh the same for every 997, so if you have knee problems or other physical limitations, drive the car and feel the weight before purchasing it. However, if it’s too late for that or you just NEED that Porsche, there are options that can help.

First, try replacing the power clutch spring. It’s a relatively cheap part and can be a quick DIY. If this doesn’t help, replacing the slave cylinder can reduce the pressure but will be more costly than changing out a simple spring. If neither of these options are feasible and you aren’t a manual snob, your best option may be to switch to a PDK (Porsche dual-clutch), or an automatic transmission.

Porsche M97 Engine Reliability

The M97 engine seen in 997’s and 987’s is, in our opinion, a great engine IF you take proper care of it AND if you have the knowledge and resources to either make a few small upgrades, or fix minor issues before they come major ones. The major issues we see from M97 engines start as small issues with the coolant system and with the oil and can be prevented, or the chances significantly decreased, with proper maintenance.

Regularly change your oil, keep an eye on coolant and oil levels and always be aware of any leaks. Drive your Porsche regularly, and let your engine get to operating temperature frequently. Doing things as small as this will help your Porsche run at a high level for a long time. This is especially important if you don’t have the finances or aren’t willing to spend the money on upgrades.

The 4 Most Common Porsche Boxster 986 Problems

June 10, 2021 by porsche Leave a Comment

The first generation 986 Boxster was released in 1996, initially intended to be a successor to the poorly selling 928. The Boxster was designed in conjunction alongside the 996 Carrera and shares many of the same parts and features. Engine design, headlights, interior comments, and the hood/front end are all shared between the 986 and 996.

The 986 Boxster lived on until model year 2005 when it was replaced by the 987 Boxster.

Boxster M96 Engine

Both first gen 986 and second gen 987 Boxsters use the M96 engine. The M96 engine came with 2.5L, 2.7L, and 3.2L displacements.

The M96 engine is a water-cooled, naturally-aspirated flat-6. The Boxster used a mid-engine layout for a lower center of gravity, improved weight distribution, and better handling. The M96 was Porsche’s first water-cooled flat fix engine

2.5L M96 Engine

The 2.5 M96 (known as the M96.20) was used from 1997 until 1999. It produced approximately 200hp and 180 lb-ft. of torque. The initial 2.5 engine had a poorly designed engine block which would cause the cylinder liners to crack. Additionally, the cylinder cracks affected the cooling systems, mixing coolant with engine oil, causing additional performance related problems and overheating.

Outside of the cylinder block design, Porsche had issues with the casting process. The cylinder sleeves were cast separate of the engine which is thought to be the reason for the cracking. Given the major issues, Porsche redesigned the engine in 1999 and increased its displacement to 2.7L.

2.7L M96 Engine

The 2.7L M96 debuted in model year 2000 as a replacement to the 2.5L. In addition to a newly designed engine block, Porsche improved upon the casting process to remediate the cylinder cracking issue. While cracking is less prone on 2000+ models, it hasn’t completely disappeared. It produced approximately 225hp and 190 lb-ft. of torque, a 25hp and 10lb-ft. increase over the 2.5 version.

Under the engine codes M96.22/23/25 the 2.7 lasted until 2006 (Boxster 987) when it was replaced with the 2.7L M97 engine.

3.2L M96 Engine

The 986 Boxster S models received a higher-output 3.2L M96 engine which produced 249-261hp and 225-230lb-ft. of torque. The 3.2 M96 also lasted in the Boxster until 2006 when it was replaced by the M97 engine, where it received a displacement increase to 3.4L.

Porsche 986 Boxster M96 Engine Problems

Rear Main Seal Oil Leak
IMS Bearing Failure
Cracked Cylinders
Cylinder Scoring

Porsche is known to be one of the most reliable car manufacturers out there, but that doesn’t mean they are perfect. While glamour, flashiness, and performance typically come along with owning a Porsche, so, too, does the price tag – not just in purchasing one but, also, in fixing one. In order to save you the hassle and the money, let’s look at some of the common problems that Porsche Boxster 986’s encounter and ways to reduce the likelihood of them occurring.

1. Boxster M96 Rear Main Seal Oil Leak

This is the main problem found amongst 986 Boxsters and typically occurs at the rear main seal on the M96 engine. The rear main seal sits where the crankshaft meets the clutch and gearbox. The seal prevents oil from the crankshaft getting into the transmission and damaging the clutch.

Unfortunately, despite numerous redesigns by Porsche, the seal is prone to deteriorating and causing leaks. While some leaks go unharmed and unnoticed, more serious leaks can destroy the clutch and other internal transmission components.

The seal can leak for a few different reasons. If you don’t drive your M96 frequently, the seal can dry out and form cracks that will cause the leak. Additionally, the air oil separator, which is an emissions system, can fail and cause the leak as well. When the air oil seperator fails, crankcase vacuum increases which sucks in excess air and damages the seal.

Rear Main Seal Oil Leak Symptoms

Burning oil smell
Engine rattling / shaking
Excess oil consumption
Shifting issues and loss of performance
Oil leaking beneath transamission

Rear Main Seal Replacement Options

Replacing the rear main seal is not expensive in itself, but oftentimes will require you to replace the clutch. It can be a hassle, though, as fixing the issue is typically not a DIY project due to the fact that the transmission and exhaust have to be removed to replace the oil seal – making the labor more expensive and intensive than acquiring the part.

The oil seal is a cheap part. It will likely leak at some point and they are meant to be replaced. The best way to prevent any damage coming from it, is to have the part replaced early. If you are having your car worked on by a mechanic for something else that requires the transmission be removed, have them replace the oil seal. Other basic preventative maintenance techniques are simply to frequently change your oil, and wait a couple minutes before turning your car off, especially after running it for a while on those hot summer days.

Using the latest and greatest seal, such as the rear main seal from LNE Engineering, can help prevent further leaks.

2. IMS Bearing Failure – 986 Boxster

IMS stands for intermediate shaft. The IMS bearing is a small piece that supports the IMS on the flywheel end of the engine. This small piece often causes large problems for Boxsters, 911’s, and Cayman’s from 1997-2008; however, due to upgrades the IMS bearing is a lot less likely to fail for models from 2006 to 2008. If this part fails, at the very least, you’re looking at having the engine removed, disassembled, and put back together. More likely, you are looking at a complete rebuild or replacement.

The IMS bearing fails for two particular reasons. First, the material that the bearing is manufactured out of is not strong enough for the amount of force and load that is exerted upon it. Second, the bearing does not receive adequate lubrication.

If you are looking at buying or selling a Porsche from 1997 – 2008 (especially pre-2016) do your homework on the car’s service history. Whether or not the car has an upgraded IMS bearing can be the reason for a large difference in its value!

M96 IMS Bearing Failure Symptoms

Metal shavings in oil
Knocking or rattling noises from the engine
Oil leaks in rear of engine

Unfortunately there aren’t necessarily any preexisting symptoms that can warn you that IMS bearing failure might occur. The most tell-tale sign of failure is metal shavings in the oil. This will generally be the first symptom to appear and then terrible performance and engine knocks all over the place will follow. And then the engine implodes, basically.

Constantly check your oil for metal shavings during oil changes. If you catch the issue early on you can likely salvage some components from your engine vs. needing a complete teardown or new engine.

IMS Bearing Replacement Options

The IMS bearing can fail at any time, regardless of mileage. Since there aren’t any warnings signs of IMS failure, our general recommendation is to upgrade the bearing before the problem occurs.

The solution to this problem is expensive, but not in comparison to rebuilding the engine. You can replace the IMS bearing with an upgraded ceramic bearing, but this will typically run you a few thousand dollars. This is also a very labor intensive project, so it’s best to do this in conjunction with another labor intensive project such as replacing the rear main seal.

IMS upgrade kits differ by engine so be sure to make sure you are ordering the proper kit before you buy. You can check out this guide to help determine what kit you need.

3. Cracked Cylinders – M96 Engine

This typically occurs for the 986 and 987 Porsche Boxsters. The liner around the cylinder cracks, usually, due to overheating from a loss of coolant. If you notice your car overheating, or your coolant running low. Fixing a radiator or a coolant hose is cheaper than replacing a cylinder. Furthermore, a cracked cylinder can lead to irreparable damage to the engine, in which case the only option is to replace or rebuild the engine.

If you see or smell coolant leaking from your exhaust or notice your coolant and oil mixing, this is a sign of a cracked cylinder. Your oil will look like chocolate milk and be gooey. Keeping an eye on your engine temp, coolant levels, and replacing your water pump before it fails are the best ways to keep your cylinder from cracking.

M96 Cracked Cylinder Symptoms

Coolant leaking from exhaust
Oil is a milky white substance
Poor performance
Smoke coming from exhaust
Low cylinder compression

4. Porsche Boxster M96 Cylinder Scoring

Cylinder scoring is one of the most common issues with the M96 Boxster and occurs when a cylinder forms deep grooves on the liner. This is usually caused by a broken or defective piston dragging across the wall of the cylinder.

If one of your exhaust pipes is way more black than the other, this is a sign that one cylinder is burning different fuel/oil mixtures. The main symptom of cylinder scoring will be a knocking noise that occurs from the piston dragging across the cylinder wall.

A lack of lubrication in the cylinder and pistons is the most common cause of cylinder scoring. It’s important to change your oil every 3,000-5,000 miles and be cautious of oil levels in between oil changes. It’s not uncommon for 986’s to consume excessive amounts of oil so check in between services and make sure oil levels are always adequate. Additionally, take it easy on your engine RPMs until it gets up to operating temperatures.

Boxster 986 Cylinder Scoring Symptoms

Black coated exhaust pipe
Knocking noise from engine (sounds like lifter tick)
Oil within the cylinders
Cylinder misfires

Is the Porsche Boxster 986 Reliable?

After reading this, you may be a little scared to spend tens of thousands of dollars on a Porsche Boxster 986. It is important to remember that no car manufacturer is perfect and no car is either. The Porsche Boxster, though, has stood the test of time. There are thousands of Boxsters for sale out there ranging in price, age, and mileage – and oftentimes the older cars with more mileage are more reliable than the older ones with low mileage.

All in all, we give the Porsche Boxster an above average grade for reliability, and well above average with an IMS bearing upgrade and proper maintenance. Spending a little more time and money on preventative maintenance will save you tons of money and stress. After all, it is a Porsche, so spending a little more on maintenance is miniscule compared to what you will spend on repairs and replacements.

Porsche M96 Engine Problems Summary

As with all cars, you can expect to replace parts from regular wear and tear, but we covered the main problems that are typically expensive to fix. At the end of the day, if you do your homework on the Boxster before you purchase one, get the IMS bearing upgrade (if needed), and take good care of your car you should expect the Porsche Boxster to run well and for a long time.

Do you have a different experience? Other problems that have occurred for you? Or tips and tricks to improve the reliability? Leave a comment and let us and other readers know!