997.2 Engine Reliability
06-13-2014, 03:36 AM
#106
Nordschleife Master
So a short version of the story is that low mileage cars that have spent most of their lives in cold climate are at increased risk?
06-13-2014, 03:21 PM
#108
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No, not broken in. Well beyond break in, at 20-45K miles, generally.
Being alarmed saves engines. I am only sharing what we see and what we've seen explode in terms of failures in the past 4 months after one of the toughest winters on record. Most of the cars that fail are C4s? Why? Because they perform very well in the snow and ice and are often driven more than any C2 would be in those conditions.
Being alarmed saves engines. I am only sharing what we see and what we've seen explode in terms of failures in the past 4 months after one of the toughest winters on record. Most of the cars that fail are C4s? Why? Because they perform very well in the snow and ice and are often driven more than any C2 would be in those conditions.
06-13-2014, 05:44 PM
#111
They are stating that because the 9a1 engine has very close tolerances, extreme cold causes the engine to contract and in those few moments it can damage the engine?
06-13-2014, 07:02 PM
#113
RL Community Team
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I drove me 2009 C2S virtually every day this awful winter with the car parked OUTSIDE. Yep, I am an abuser....
What I found, is that I am using less and less oil as the car ages. 57K miles now.
Peace
Bruce in Philly
What I found, is that I am using less and less oil as the car ages. 57K miles now.
Peace
Bruce in Philly
02-12-2015, 05:47 PM
#114
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I thought to add my own investigation and conclusions... this was a very early investigation about Porsche‘s 9A1 engine (not the DFI version mind you):
The secret behind the exhaust smoke upon startup 2.9L Caymans - An inconvenient truth
The secret behind the exhaust smoke upon startup 2.9L Caymans - An inconvenient truth
02-12-2015, 05:53 PM
#115
Rennlist Member
I thought to add my own investigation and conclusions... this was a very early investigation about Porsche‘s 9A1 engine (not the DFI version mind you):
The secret behind the exhaust smoke upon startup 2.9L Caymans - An inconvenient truth
The secret behind the exhaust smoke upon startup 2.9L Caymans - An inconvenient truth
02-13-2015, 02:22 PM
#116
02-13-2015, 03:31 PM
#117
Rennlist Member
I thought to add my own investigation and conclusions... this was a very early investigation about Porsche‘s 9A1 engine (not the DFI version mind you):
The secret behind the exhaust smoke upon startup 2.9L Caymans - An inconvenient truth
The secret behind the exhaust smoke upon startup 2.9L Caymans - An inconvenient truth
02-15-2015, 09:56 AM
#118
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And, although high pressure fuel pump issues and the DFI system itself when running overly rich could potentially lead to fuel intrusion and cylinder wall 'wash' (see picture below) with bore scoring being the end result, which would match the cold weather theory nicely since with cold temperatures the engine tend to run with richer air/fuel mixture, my experience with the 987.2 Cayman was different and all came down to Porsche's poor quality control!
So, the major conclusion is: if bore scoring exists independently of its cause you'll see smoke (withish with a blue haze) from the tail pipe upon startup. Moreover, since the 911 has independent exhaust flow paths one can clearly determine which cylinder bank is affected. That would be the one that smokes.
Looking at this picture and if the 'cold weather theory' is correct I would expect that bank 1 (cylinders #1,2 and 3) would be the most affected since the fuel injector points downwards directly to bank 1's cylinders thrust side, where most of the force is exerted by the piston on its power stroke (one would occasionally see smoke upon startup from the left tailpipes when looking from the rear end of the car - cylinder bank 1):
I think Flat6 Innovations can chime in and tell us which cylinders are the most affected. I have just found this:
It's hard to work out where the value is in telling the story. In other words, with no real explanation of what caused the problem I can't relay information that would help others.
The car is my C2S 2008 and had done just under 16k when I bought it. A month and about 1,000 miles later the engine was in trouble. When it 'happened' the car flashed up a warning and told me to drive it to the workshop. The drive had been unremarkable up to then.
I felt it.was using more oil than my 996s had; needed a litre in 1,000 miles. Indeed our 997 C4S hasn't needed any in similar mileage.
I got it recovered to the OPC and they boroscoped it. Cylinder 3 showed some heavy scoring. Once it was dismantled you could see matching scoring on both sides of the corresponding piston. The five remaining bores looked perfect.
I didn't see much evidence of other afflicted cars when Googling. But given 90% of the people that own these probably don't go near Internet forums, I'm not sure what that proves.
I skipped Gen 1 997 in the hope of avoiding engine woes. Hopefully the C4S will be fine and I'll be half right.
The car is my C2S 2008 and had done just under 16k when I bought it. A month and about 1,000 miles later the engine was in trouble. When it 'happened' the car flashed up a warning and told me to drive it to the workshop. The drive had been unremarkable up to then.
I felt it.was using more oil than my 996s had; needed a litre in 1,000 miles. Indeed our 997 C4S hasn't needed any in similar mileage.
I got it recovered to the OPC and they boroscoped it. Cylinder 3 showed some heavy scoring. Once it was dismantled you could see matching scoring on both sides of the corresponding piston. The five remaining bores looked perfect.
I didn't see much evidence of other afflicted cars when Googling. But given 90% of the people that own these probably don't go near Internet forums, I'm not sure what that proves.
I skipped Gen 1 997 in the hope of avoiding engine woes. Hopefully the C4S will be fine and I'll be half right.
Last edited by CaymanPower; 02-15-2015 at 04:42 PM.
02-15-2015, 10:17 AM
#119
Former Vendor
I think Flat6 Innovations can shime in and tell us which cylinders are the most affected.
My last 5 years have been spent researching and developing the 9a1 engines, both DI and port injected. With these I am not making the same mistakes that I made with the M96/97 engines, and sharing what I've learned online. People don't want to hear the truth, they just want to believe that its all Unicorns and rainbows in the mechanical workings within their engines. Most of them don't even believe problems can occur when their own engine snaps a timing chain and blows it through the cam cover; they certainly won't believe anything thats written.
There's a reason why we bought a new car in early 2010 and took the engine apart straight away. My record is pulling a 9a1 apart with 11 miles on the odometer.
02-15-2015, 10:52 AM
#120
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As a developer who shared what he learned, in a forward and direct manner with the M96/ M97 engines, I caught a lot of flack. Terms like "fear monger" didn't sit well with me.
My last 5 years have been spent researching and developing the 9a1 engines, both DI and port injected. With these I am not making the same mistakes that I made with the M96/97 engines, and sharing what I've learned online. People don't want to hear the truth, they just want to believe that its all Unicorns and rainbows in the mechanical workings within their engines. Most of them don't even believe problems can occur when their own engine snaps a timing chain and blows it through the cam cover; they certainly won't believe anything thats written.
There's a reason why we bought a new car in early 2010 and took the engine apart straight away. My record is pulling a 9a1 apart with 11 miles on the odometer.
My last 5 years have been spent researching and developing the 9a1 engines, both DI and port injected. With these I am not making the same mistakes that I made with the M96/97 engines, and sharing what I've learned online. People don't want to hear the truth, they just want to believe that its all Unicorns and rainbows in the mechanical workings within their engines. Most of them don't even believe problems can occur when their own engine snaps a timing chain and blows it through the cam cover; they certainly won't believe anything thats written.
There's a reason why we bought a new car in early 2010 and took the engine apart straight away. My record is pulling a 9a1 apart with 11 miles on the odometer.
Can you please at least tell us what in your experience are the most affected cylinders?
Last edited by CaymanPower; 02-15-2015 at 11:17 AM.