YACT: Bluish smoke upon start

tontod

Diamond Member
Oct 12, 1999
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I have a 99 Audi A4 1.8T quattro (tiptronic). It just hit 100k yesterday. The last few days I've noticed that when I start the car, I see bluish smoke billowing out the exhaust for about 15-20 seconds then dissipates. It only seems to happen when I start the car after the car has been sitting for at least an hour. It does not do it every time, even when it hasnt been driven in a while. Anyone have any ideas?
 

tontod

Diamond Member
Oct 12, 1999
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Are they easy or hard to replace? I'm guessing the gasket isnt expensive, but labor might be depending on location?
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
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Could also be rings...

Blue smoke = oil burning.

Not a good sign on an engine with only 100k.

When was the last time you changed your oil?
 

tontod

Diamond Member
Oct 12, 1999
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I thought it was burning oil, but I had it changed earlier today. Afterwards, I went to a neighbor's place, had the car parked for an hour. Upon starting it up, I saw smoke. Since it was dark outside, I couldnt tell the color, but I could definitely see the smoke.
 

Vic

Elite Member
Jun 12, 2001
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Leaky oil seals in the turbo. I'm 99% certain of it. No real big deal either. It's unsightly and does mean the turbo will eventually fail (someday) but won't affect performance except for the fact that oil is decidedly "low octane." To confirm this, pull the outlet hose on the cold side of the turbo and look for oil residue, or pull the downpipe on the hot side and look for the same. Turbos are no longer very expensive to replace and, given the miles on the car already, I would suggest getting a lower-miles used one instead of new.
 

SuperSix

Elite Member
Oct 9, 1999
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If it's only on startup - it's the valve seals. Not cheap to fix (labor$$$), but nothing to really worrry about.

*I* wouldn't spend the $$$ to fix it, I would just keep driving it.
 

pac1085

Diamond Member
Jun 27, 2000
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probably the turbo. you're very lucky to have got to 100k on the stock turbo. oil was leaking into my turbo on my 97 a4 once it hit 50k miles and died (wastegate problem) at 55k.

the oil leak was so bad, when i pulled the hose off the intercooler oil poured out.
 

thedarkwolf

Diamond Member
Oct 13, 1999
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I'd go along with the don't bother fixing it people. If its the valve stem seals it really doesn't hurt anything and if its the turbo it doesn't sound bad enough to worry about yet. My old galaxie had NO valve stem seals by the time I got around to rebuilding it but it still ran fine and didn't burn much oil other then at startup but at start up it was like I was James Bond flipping the smoke screen switch :).
 

iamwiz82

Lifer
Jan 10, 2001
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I noticed that you just changed it, did you spill some on the engine, perhaps the exhaust manifold or pipe?
 

IonYou

Banned
Jul 28, 2005
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Originally posted by: iamwiz82
I noticed that you just changed it, did you spill some on the engine, perhaps the exhaust manifold or pipe?

lol that wouldnt cause bluish smoke to come out of the exhaust
 

tontod

Diamond Member
Oct 12, 1999
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Originally posted by: iamwiz82
I noticed that you just changed it, did you spill some on the engine, perhaps the exhaust manifold or pipe?

I had it done at a mechanic. I was getting the smoke before the change and after. Not sure if they spilled some or not.
 

tontod

Diamond Member
Oct 12, 1999
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I might let it be, but the thing is I have an emissions inspection coming up in a few days. I wonder if it will pass emissions.
 

91TTZ

Lifer
Jan 31, 2005
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Originally posted by: tontod
I have a 99 Audi A4 1.8T quattro (tiptronic). It just hit 100k yesterday. The last few days I've noticed that when I start the car, I see bluish smoke billowing out the exhaust for about 15-20 seconds then dissipates. It only seems to happen when I start the car after the car has been sitting for at least an hour. It does not do it every time, even when it hasnt been driven in a while. Anyone have any ideas?


You mention you have a turbo, and this is a common problem for worn turbos. The seals on the turbo get worn and oil seeps past them when the car is off. When you start it up, it burns up and you see smoke.
 

Quixfire

Diamond Member
Jul 31, 2001
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Originally posted by: 91TTZ
Originally posted by: tontod
I have a 99 Audi A4 1.8T quattro (tiptronic). It just hit 100k yesterday. The last few days I've noticed that when I start the car, I see bluish smoke billowing out the exhaust for about 15-20 seconds then dissipates. It only seems to happen when I start the car after the car has been sitting for at least an hour. It does not do it every time, even when it hasnt been driven in a while. Anyone have any ideas?


You mention you have a turbo, and this is a common problem for worn turbos. The seals on the turbo get worn and oil seeps past them when the car is off. When you start it up, it burns up and you see smoke.
Oil burning from the turbo seals usually only happens on the intake side of the turbo. The exhaust side is after combustion and the oil wouldn't burn off. If you have noticeable oil loss and no visible leaks on a turbo charged car I always check the exhaust side of the turbo for leaks.

Tontod,

Leaking valve stem oil seals causes most blue smoke on start up concerns. The reason is when the engine is shut off the oil in the valve area puddles around the bottom of the valve springs. As the seals wear they allow more oil to enter the valve guide and leak down into the combustion chamber. Once you restart the engine the oil is burned off, bluish-white smoke, and the engine will run fine. As the engine ages further the concern make last longer and sometimes can get tot he point where it's burning oil all the time. The cost to repair this depends on your mechanic. If he feels new valve stem seals are all you need then the price to replace them could be $200-300, if he feel the cylinder head needs to be reconditioned because of worn valve guilds it could be $800-1100 depending on the amount of work that needs to be done.

Good Luck,
Quixfire