dhamilton

Hey all,

I bought a '95 Audi 90 Quattro Sport back in February. It's a higher-mileage car (131,000) and I drive it pretty hard on lots of long-distance cross-country treks. I am very mindful of the oil level, and when I first got it I noticed that it was eating maybe a quart every thousand miles...not great, but not mind-numbingly terrible. I normally do all my own oil changes and tuneups, but at one point I got stupid and took it to a Jiffy Lube because I didn't have the time to do it myself, and after I got it back from them it was spitting big clouds of blue smoke out the tailpipe. I don't know if they were just using ****ty oil or what, but I took it back after a few days and they did another change, to a higher-grade oil. The problem got better but didn't go away, so a few days later I made some time and did another change myself, and the rate of consumption went back to normal. I usually use 10W-40 non-synthetic; the Jiffy-Lube guys put something a lot thinner in. Once I went back to that everything was fine. This made me think that perhaps the piston rings are getting worn, but are still good enough for thicker oils.

However, on the way back from a recent trip to Montana (from California), I noticed the oil consumption starting to skyrocket. I was having to put in two quarts every gas tank. On top of that, I started noticing a thin, bluish-white smoke (I've been trying to tell the color of it since, and it's a bit of a bluish-white, but it's so thin it's hard to tell) coming from the bottom of the engine compartment after driving. It's thin, but there's enough of it that when I'm stopped at stoplights I can smell it and see it if the light is right. As near as I can tell, there is little or no blue oil-burning smoke coming out of the tailpipe. In addition, I notice when I pull the oil dipstick the same whitish-blue smoke coming, very thinly, from the dipstick tube. Whuhhh?

There are, also, no oil stains on the driveway after I park it overnight, just a few drops. I have a few theories
*a leak somewhere in the oil pump, so that it only leaks when it's running, and the smoke I see is oil burning off of some piece of hot engine casing?
*leaky valve or camshaft seals, letting oil get into the cylinders and burn there. If this is it, why does the smoke come from the engine bay, and not the tailpipe?
*bad piston rings. Same question as above.

What else might be causing something like this? Could a bad EGR or PCV valve, in addition to bad piston rings or valve seals, be allowing oil burnt in the cylinders to escape into the engine bay?

I've got most of the right tools and do most of my own repairs, but have never attempted to pull pistons and replace rings. I'm trying, however, to stay out of repair shops as much as possible for this one.

Thanks!

Daniel

4000fixes

If you have smoke...then its your rings. Use 20w-50. itll help. ive used it forever.

SCarGo02

...I've never had a 12V that did any of what you're describing -- some of them had a lot more mileage than what's on your car. Try the 20W50 as 4000fixes suggested see if it helps.

12Vs are known for leaks and I have seen some smoke from excessive leaking burning off hot engine/exhaust bits after long/hot drives.

I'd also degrease any oily messes (especially in the valley pan area) and go from there...

Jretal

my guess is that if you're smelling burning oil when coming to a stop, your valve cover gaskets/cam shaft seals are leaking. These can be a pretty bad source of a leak.

That being said, if your seeing blue smoke, either the rings or the valve stem seals are going.

Clean the engine really well and then keep an eye out for oil leaks and see if you can pin point them.

I have over 186k miles on my 12v, and it's running like a top. That being said, I've replaced almost all the oil seals at least once:

1) valve cover gaskets (x2)
2) cam shaft seals (x3)
3) valley pan gasket (x1)
4) lower oil pan gasket (x1)
5) oil cooler o-ring (x1)

the only other gaskets I haven't replaced are the upper oil pan gasket (doesn't need it) and maybe an o-ring here or there around a sensor.

That being said, if you're seeing blue smoke out the tail pipe even w/ your oil changes done, you might have ring or valve stem seal issues. I'd take a guess that you saw the blue smoke from jiffy lube b/c they overfilled it. You check the oil level before giving it back to them?