The 4 Most Common Porsche M97 Engine Problems
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.
Great job summarizing the issues with the M97 engine. I’ll just add that for the IMS issue, having the grease seal removed is recommended to help extend the life of the non-serviceable 06-08 intermediate shaft issue.
LN Engineering has extensive information regarding how to prevent IMS and cylinder bore scoring issues with these models that every owner or someone considering purchasing a Porsche with an M97 engine should read.