1. Home
  2. Audi Cars Forum
  3. 95 Audi 90 Quattro Oil smoke in exhaust.

95 Audi 90 Quattro Oil smoke in exhaust.

I have a 1995 Audi 90 Quattro with 165,000 miles.

This morning I noticed a small cloud of smoke that I left at an intersection when I pulled out. When I got to work I opened the door and pressed on the gas and watched a faint (not opaque) cloud of oil (not water) smoke form behind the car. This was more than a little disturbing.

From what I know, this could be coming from a head gasket, piston rings or valves? How might I decide which is the cause?

Of course, after coming home from work, I could not reproduce the symptoms. Sticky piston ring?

Gene

Reply to
Gene
Loading thread data ...

I think I've learned another detail about this. I saw the same puff of smoke at the same intersection this morning. I realized that this stop sign is at the bottom of a hill that I coast down in gear using the engine to gently limit my decent. It would seem to me that, in this condition, I may be sucking oil past rings or valves into the combustion chamber without buning it while I coast down the hill, then it burns under accelleration. It's been suggested to me that these engines don't tend to wear piston rings or cylinder walls much at all. So, I guess I'm looking at valve guides?

Gene

"Gene" wrote in message news:Vk0kb.878$ snipped-for-privacy@newsread1.news.atl.earthlink.net...

Reply to
Gene

Gene, You might try a "leakdown test" - I believe that may tell you if the leak is through the rings (= "blow-by"). In an intake vacuum condition - throttle body closed, engine winding away to slow the car, I would expect it to the valve guides as well. Cheers! Steve Sears

1987 Audi 5kTQ - valve guides replaced with head gasket....one of those "while you're at it" things. 1980 Audi 5k - goesn't burn oil so much as leak....darn cork-shrinking synthetic oil.
Reply to
Steve Sears

Pulling the heads and replacing valve guides (and all the gaskets) seems to have cleared this all up.

A point of interest: All 6 cylinder walls still have visible original factory cross-hatching. The engine has 180,000 miles on it! I expect I'll be driving this for a long time to come....unless I decide to get a 30V A4 some day.

accelleration.

Reply to
Gene Buckwalter

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.