Corolla burning oil - advice needed

Are you sure you don't have an oil LEAK? That is a lot of oil to burn in 2000 miles.

It is impossible to tell who is correct without seeing the engine first hand. 3 quarts of oil every 3,000 miles is a LOT of oil, and I would imagine that if the engine is burning the oil, you would see clouds of smoke coming out of the exhaust at startup or heavy acceleration.

If the third Toyota technician found that the plugs are clean and do not have an oil residue, I'd suspect that the oil is leaking somewhere. A lack of tune-up will not cause the car to burn oil, although lack of routine oil changes can.

Thanks for your replies. I changed oil regularly on it, around every

Neither of the three mechanics could find any oil leaks in the car. Some time exhaust gas looks white, especially in winter, I've seen a cloud of white smoke coming on startup. Rear bumper is covered in some black stuff above the exhaust pipe but the third mechanic said it was soot from rich mixture, not oil in exhaust.

How to detect oil leak? I have been paying attention to the garage floor but never seen oil drips on it.

Is it possible to ask them to conduct some tests, like compression or something, to prove their diagnosis?

thanks, Sergey

The cloud of smoke at startup seems to indicate leaking valve stem oil seals, as does the sooty buildup on the bumper. If the mixture were too rich, the vehicle's on board diagnostics system should catch the improper air/fuel mixture.

Those clues (clouds of smoke at startup) are important ones that you need to share with whoever is diagnosing the car if they did not specifically ask you.

It is possible to check for bad rings and elongated cylinders with compression and leakdown tests. Fortunately, valve stem oil seals are less expensive to replace. Ask your technician to check them out.

Ray,

The mechanics did not ask me about the smoke or the soot. They didn't mention valve stem seals either. I will talk to them about it.

When I hear about $2700 worth of repairs I am becoming very distrustful :) One last question to you:

- Can mechanic run some tests or a visual inspection to diagnose valve steam seals? If a mechanic says "I am sure it is cylinders not valves" or the other way around, how can they corroborate their statement?

thanks, Sergey

If you left your car overnight at the service facility and the mechanic was able to start it up and see the smoke himself, then he didn't have to ask. If you did not leave your car overnight, then the mechanic should have asked you if you noticed smoke coming out of the exhaust. Likewise, he may have noticed the sooty buildup on the bumper.

there are several ways to check whether oil is leaking past the valve stem seals. If the service facility has a borescope, they can remove a spark plug and actually look inside the cylinder and see if there is oil pooled on top of the piston after being parked overnight. If the service facility does not have a borescope, they can still park it overnight and start it up in the morning and see what comes out the exhaust.

As I mentioned before, it is possible to check rings and cylinders by doing compression and leakdown measurements.

They can show you the results of their compression and/or vacuum gauge tests. These are sort of "old school" diagnostics & don't know whether anyone uses them anymore in these days of OBD readers.

Compression, leakdown, and vacuum gauge readings are still very useful although in this case, manifold vacuum will not point out the cause of the leak.

I have enough to go talk to the mechanics now. Thanks a lot for your help!

Sergey

You're welcome and good luck!

I have the same problem with my Toyota. My 99 Corolla has 113K miles on it and burns oil as well. I've seen several mechanics and all said that the problem would be stuck rings, major engine problems, things I'm not ready to pay for. I've tried oil additives, cleaners, etc... Nothing seems to slow the burning and I know there are no leaks. My back bumper is graying from the burning, and while I don't see puffs of smoke when I start up the car, I see it when I'm driving on the interstate and the car downshifts to passing gear. Would you mind keeping me up to date on your findings? I thought my Corolla was the only one with this problem.

Thanks

Ray O wrote:

Unfortunately, smoking when downshifting is an indication of ring problems.