Puff of smoke on startup

[vikingrs6]

I remember those posts. How was the oil getting into the cylinders? Throught the sparkplugs? How come you had smoke coming from both sides though, but managed to fix it with one rocker cover gasket?

I only had smoke from one side. Think that the cylinder pressure coming back round the ill fitted spark plug, being bunged by the ignition coil might have caused the seal to be pushed back into the cam cover as the point is least resistance if that makes any sense?!.. That seemed to cause the oil to get into the spark plug chamber and seep into the cylinder - on next start up got the smoke.

Not sure I've explained it very well but the images on the post I linked to show the cam cover casket around the spark plug chamber..

[Shoppinit]

OK, that makes more sense. I had understood that you were getting smoke from both sides. Hopefully both my rocker covers aren't leaking - no sign of oil, but I haven't really been looking.

[vikingrs6]

OK, that makes more sense. I had understood that you were getting smoke from both sides. Hopefully both my rocker covers aren't leaking - no sign of oil, but I haven't really been looking.

Mine had obvious seepage from the coil pack as on the picture but only noticed when I had a proper look. You'll need to take the coil packs off to check properly. You will see oil around the plugs. The one I had the issue with was literally swimming in it.

[Shoppinit]

I need to change the plugs soon anyway, so I will have a good look then. I am always loath to remove the airbox unless I have to. THanks for the tip, anyway.

It does seem really unlikely that oil could get past the sparkplug gasket, though, without causing all sorts of other engine problems, but you are the proof it can happen!

[vikingrs6]

It does seem really unlikely that oil could get past the sparkplug gasket, though, without causing all sorts of other engine problems, but you are the proof it can happen!

I know it was suprising, if you look at the image below you can see that the left hand gasket is sunken into the camcover compared to what it should be like on the right. You can see the oil around the spark plug..

[Shoppinit]

Oh yeah, so it is. How did that happen?!

[vikingrs6]

Oh yeah, so it is. How did that happen?!

My assumption is due to the spark plug not being tight, gases where getting past the plug and as the coil packs are snug the gasses had only one place to go - push the gasket seal into the cam cover like the picture. Knock on effect allowing oil the get back past the coil pack and seep into the cylinder. When I had my issue I did find a guy in the US that had exactly the same thing happen..

[Nobby]

Just to note: Not saying this is your problem but it still could be.

Turbo seals can go on both the inlet AND outlet side.

On my car its fairly common for the standard turbos to go on the exhaust side, so as soon as you turn off the engine a tiny pool of oil sits inside the turbine. As soon as you start the car it burns off instantly with a little puff from the exhaust. Its a sign of wear though, and depending on how bad it is mine once lasted for another 20k miles without trouble. Many Coupe owners have upgraded to roller bearing turbos which seem to be less prone to this damage, require little (or none) backpressure to keep the seals doing there jobs.


Any chance you can whip off a downpipe and check out the turbine? If there is oil in there then it is definately the turbo.

[Shoppinit]

Any chance you can whip off a downpipe and check out the turbine? If there is oil in there then it is definately the turbo.

Just as soon as the engine is removed.

This is an RS6 - the engine has to come out for everything bar the spark plugs, pretty much.

[Nobby]

Oh yeah, so it is. How did that happen?!

My assumption is due to the spark plug not being tight, gases where getting past the plug and as the coil packs are snug the gasses had only one place to go - push the gasket seal into the cam cover like the picture. Knock on effect allowing oil the get back past the coil pack and seep into the cylinder. When I had my issue I did find a guy in the US that had exactly the same thing happen..

Sorry I can't view your photo from work PC, but, could it not also be the case that under a positive crank case ventilation system you are getting blow-by (from spark plug > past coilpack >into cam cover - you could also get this from worn piston rings etc....) which is causing excess oil vapour to be pushed into your inlet?

[imacool]

Any chance you can whip off a downpipe and check out the turbine? If there is oil in there then it is definately the turbo.

Just as soon as the engine is removed.

This is an RS6 - the engine has to come out for everything bar the spark plugs, pretty much.

Hi Shop,
How did you solve the problem with smoke on startup?
Mine does the same, a puff of white/grey smoke on ignition, literally one puff and does not do it all the time. It seems the longer the car sits unused the less the chance of smoke. After I came back from my holiday I started the car and nothing happened. Then the other day, in the morning, it smoked again. Next day in the morning-nothing.
No other issuses with engine, no misfiring. Coolant level unchanged.
For now it may only be embarassing sometimes (underground garages...), hope it's nothing serious.

[Shoppinit]

I've decided it's normal. Not worrying about it.

[imacool]

I've decided it's normal. Not worrying about it.

[adsgreen]

I've decided it's normal. Not worrying about it.

There's an acronym from the Lotus world that I think is appropriate here when taking a car back to a dealer with a problem.
"TADTS".
(They all do that sir)

[imacool]

Hi guys, quick update to my "puff of smoke on startup".
Mine used to smoke for about half a second from outside (driver) tailpipe. What was strange it didn't smoke when the car was stationery for few days, but it always did when I restarted the engine after few hours, within the same day. Blue/grey smoke, smelled like burnt oil.

Last Tuesday I had my car inspected and serviced (20K service at 103k) by MRC. After removing sparkplugs they found that the one from the front cylinder, outside, was what they called "contaminated". And when they inspected the cylinder with a borescope camera, they found a small amout of oil in the front cylinder, outside. They took me into the workshop to show me that. All other cylinders were fine, compression test OK.

They've completed the service, put new oil and plugs in and then I had a chat with Dough about what could be behind the oil in one cylinder. He mentioned leaking turbo,piston oil scraper ring or valve stem seal. My engine had some boost spikes as they found on Vagcom, which turned out to be faulty N75. After they replaced the N75, boost went back to normal, but Dough said those spikes might have worn the turbo a bit which then could lead to some oil leak into the intake and then into the first cylinder.

Anyway, he recommeded to wait and see what happens, to check oil consumption and eventually review and reinspect the cylinder again after few hundreds miles as he said it might also be the wrong or low quality oil that was in the engine previously. Before MRC all the service work was done by Tonbridge Audi, except the last one which was done at 93k.
At the moment the car is still smoking a bit, although it is not as bad as it used to be. No misfiring, no rough idling, no other symptoms. Mileage 103K.

Has anyone of you guys come across this issue before?