puff of white smoke from start up on warm engine?

[sw388]

Been searching and ended up kind of stumped. Seems like everyone that has white smoke on start up are usually from sitting over a period of time from a cold engine.

My car doesn't smoke at all when completely cold, but after driving and stopping with the engine fully. The next start up on the warm engine will puff a white cloud of smoke then go away right after.

This makes me wonder, if it is indeed burning coolant, why is it leaking on a warm engine when all gaskets are expanded?

Any Ideas?

[EUROSWAGR]

It's oil leaking past your valve stem seals when it's warm. Then when you go to restart it the puff of smoke is from the oil that gets into the cylinder or on top of the intake valves burning up.

Pull all of your plugs and see if any are covered in oil.

I had a problem with intake seals in cylinder 3 and 8 at 68k miles. I replaced all 40 valve stem seals and smoking issue went away completely.


Are you loosing coolant? if not then it isn't a coolant issue.

[sw388]

been checking the coolant. Doesnt look like I'm losing any coolant.

I'll pull the plugs and check. But if it was the intake seals, and I was to replace all valve stem seals, that would require to pull both heads completely correct?

its a 06 s4 btw with 52k miles

[TarlCabot]

been checking the coolant. Doesnt look like I'm losing any coolant.

I'll pull the plugs and check. But if it was the intake seals, and I was to replace all valve stem seals, that would require to pull both heads completely correct?

its a 06 s4 btw with 52k miles

depends on the condition of the plugs, head/s would have to be pulled and not really worth trying to do it while in the car, so motor and trans would have to be pulled

IMHO... check your oil level 1/2 dipstick = 1 quart/liter, dipstick dry = 2 or more quarts/liters, monitor it closely, oil light will only come on after 2+ low

[JimmyBones]

been checking the coolant. Doesnt look like I'm losing any coolant.

I'll pull the plugs and check. But if it was the intake seals, and I was to replace all valve stem seals, that would require to pull both heads completely correct?

its a 06 s4 btw with 52k miles

Euro is right that it is probably valve stem seals.

The Bentley manual instructs removing the engine, taking off the timing chains from the camshafts, removing the camshafts, and then using a few special tools to replace the valve stem seals with the cylinder heads still on the engine. I am currently in the process of getting the special tools because I need to change out the valve stem seals on my mother's A4 but the main expensive tool set VAS 5161A is out of stock at the moment because they are doing a major shipment to all the local Audi dealerships. I personally think that the valve stem seals can be replaced on most all Audis with the engine still in the car if you can get the camshafts out but you need the kickass special tools to do it. The valve stem seal puller comes apart so that it can be used in tighter spaces and when you combine that with being able to finagle the engine around to get more room it seems possible but I doubt most shops would be willing to try.

If you could DIY then it would also be a good idea to do cylinder leakage tests at cold and then warmed up to operating temperature. Just to rule out scored cylinder walls and oval shaped pistons.

[ess_four]

I thought that a blue and not white puff of smoke on start up after some time indicates valve stem oil stems.

[Dirtracer603]

I thought that a blue and not white puff of smoke on start up after some time indicates valve stem oil stems.

It tends to be white with a hint of blue upon closer inspection....

[sw388]

Looks like I might need to rule out my issues. It just might be a hint of blue ^

Not losing coolant but just checked the oil this morning. Was about 1/4 line on the oil dipstick as where roughly 2 weeks ago it was at the 3/4. I usually lose 1 quart of oil over a month of driving..now it seems like its burning a quart in 2 weeks.

not looking good..maybe a leakage test is next. The cars only got 52k miles too, lets hope for good news