700 mile babied 997.2 RS sometimes puffs smoke upon start up?
10-06-2011, 07:26 AM
#16
Rennlist Member
Hey Joe, a couple theories have been floated here in the past... The one that seems to explain it best is that your cylinders sit horizontally so on shut down some oil makes its way to the bottom of the cylinder (lowest point) and sometimes past the piston rings... On start up, wateva is on the combustion side comes out as smoke... It has been suggesting that letting it idle for a minute before shutdown gets rid of access oil accumulation in the cylinders which may seap past rings...
10-06-2011, 07:31 AM
#17
Rennlist Member
I'd also like to know what is the cause of the noise Nugget describes so eloquently in his 3rd bullet. I hear this same noise coming from the rear often on start-up after the car has been unused for several days and it is scary. It sounds like something is self-destructing back there.
Hello
Regarding startup smoke I have noticed that it will not smoke if I idle the car for 2 minutes before shut down. I also do believe that 5W40 oil instead of 0W40 will decrease the puff-smoking. Both oils are approved by Porsche so nothing to worry about.
Regarding the clonk noise 2 sec after starting which to me sounds like clonk+grrrrrr (clonk + grinding noise) will disappear if the clutch is depressed longer than 2-5 sec. I was convinced the noise came from the AC compressor clutch as it engages 1-2 sec after start-up but that was not the case. The noise must therefore come from the clutch/gearbox area but I cannot understand what the reason is. Dealer tells me it is the clutch and it is normal (car is a RS 2008 with only 4500km only). What could cause this noise in a clutch ?
wbr/Peter
Regarding startup smoke I have noticed that it will not smoke if I idle the car for 2 minutes before shut down. I also do believe that 5W40 oil instead of 0W40 will decrease the puff-smoking. Both oils are approved by Porsche so nothing to worry about.
Regarding the clonk noise 2 sec after starting which to me sounds like clonk+grrrrrr (clonk + grinding noise) will disappear if the clutch is depressed longer than 2-5 sec. I was convinced the noise came from the AC compressor clutch as it engages 1-2 sec after start-up but that was not the case. The noise must therefore come from the clutch/gearbox area but I cannot understand what the reason is. Dealer tells me it is the clutch and it is normal (car is a RS 2008 with only 4500km only). What could cause this noise in a clutch ?
wbr/Peter
10-06-2011, 11:07 AM
#18
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I know what you mean with hydraulic tappet noise but this is not what I am refering to. I had that on my 996 GT3 and that was solved by changing to 5W40 oil. The clonk-grrrr sound I am refering to is definately coming from clutch/gearbox as it is not heard if I keep the clutch depressed 5 seconds. This happens only if the car is parked more than 24 hrs.
10-06-2011, 01:38 PM
#19
My .2 RS smokes on every start after sitting overnight, and sometimes after restarting after sitting less than an hour. My .1 RS and my 6 GT3 never smoked except after sitting for weeks. I'm keeping an eye on the .2 RS and already filed a warranty claim. While not uncommon, not sure it's a good thing.
10-06-2011, 01:41 PM
#20
I'll typically let the car sit at idle for 1minute before shutting it down....... that seems to make a big difference in any puffs on your next start. (Typically worse if hitting a hill or steep driveway, or just after an AutoX session and hard corners....... but let it idle for at least a minute and see what happens)
10-06-2011, 02:58 PM
#21
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That grinding noise is from the chain tensioner. A lot of discussion was had here when the 997.1 was released 4 years ago. Letting it sit idle for a minute or two before shutting down does not seem to correlate to how the tensioner responds the next time you start the engine. That is my experience.
Letting the engine idle for a minute seems to cut down on the smoke upon next start-up.
Letting the engine idle for a minute seems to cut down on the smoke upon next start-up.
10-07-2011, 01:46 AM
#23
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That grinding noise is from the chain tensioner. A lot of discussion was had here when the 997.1 was released 4 years ago. Letting it sit idle for a minute or two before shutting down does not seem to correlate to how the tensioner responds the next time you start the engine. That is my experience.
Letting the engine idle for a minute seems to cut down on the smoke upon next start-up.
Letting the engine idle for a minute seems to cut down on the smoke upon next start-up.
10-27-2011, 06:57 PM
#25
Chiming in late. I get all of the above, but am surprised more discussion isn't found on the strut tower noise, which correlates to cold weather. It's just starting to come back in the 40-50 degree weather, like someone said. Dealer had no idea what it was. Loud BANG goinb over even smaller potholes, sometimes.
I get the oil smoke thing, but have to say it smells more metalic than my old 3.2. Then, I was convinced it was just smoke.
I get the oil smoke thing, but have to say it smells more metalic than my old 3.2. Then, I was convinced it was just smoke.
