Incredible disappearing oil mystery - 2001 Corolla

Look around the oil pan. As I have said here before, I had two Corollas that suffered from the oil pan loosening. Same thing: no oil-fouled plugs, no dripping, no blue smoke, etc, but a thick sludge around the oil pan.

It only 'escapes' when there is enough pressure to force it past the seals. So, when you're driving on the highway, you're probably leaving a trail (ever so slight) of oil behind you...

PCV valve?

PCV valve is fine. I will check for a sneaky oil pan leak. Keep the ideas coming folks - I appreciate them all.

"Artesia" wrote: > Three months ago I purchased a 2001 Corolla with 80k on it. I > have now discovered that it burns oil to the tune of 1 quart > per 200 miles. Please consider the following facts: The car > runs great. It has no oil splatter anywhere underneath or > under the hood. The parking spot is completely free of any > drippings. There is absolutely no blue exhaust even on initial > startup. Compression tests on the cylinders revealed 200 psi > per cylinder (book says 145 min. 218 max.). The spark plugs > did have white ash on them but were dry and not eroded. This > is mind blowing, where is all that oil going??? 8O

I can't imagine how a quart could disappear in only 200 miles and you can't see it coming out form somewhere -- either on the ground or out the tail pipe.

The key to compression testing is that all cylinders be the same -- within about 10% of each other. If you have that, then you have good rings.

I was waiting to see if anyone provided a good clue, and Hachiroku seems to be the closest. Based on the condition of the spark plugs, compression test results, and lack of blue smoke, I'd guess that the oil is leaking out somewhere or getting into the coolant. Check the condition of the oil to make sure it does not have a milkshake appearance and make sure that there is no oil mixed with the coolant.

Look for leaks around the oil pan, valve cover gasket, head gasket, oil filter, and crankshaft seals.

The Supra had a loose pan, too. But that's not all. A leaky valve cover gasket makes itself quite apparent...if you have a sense of smell!

The valve cover gasket is leaking SO bad that after a run from Deerfield to Brattlebor you could see the smoke coming out from under the hood! It was a lot worse before I tightend the nuts (of course I went cross-cross!) but it still is visible if you're looking...or after you get a good whiff!

That will be a project for next week or the week after...along with new plugs and wires. The wires are corroding from the oil!

"Jeff Strickland" wrote in news:3ICdnQEvuuLmkAXYnZ2dnUVZ snipped-for-privacy@ez2.net:

Beg to differ with you but good compression does not always equal good oil control. You can have stuck oil control rings w\ fully operational compression rings & therefore burn oil. Each piston has oil control rings & separate compression rings. dc

I also can?t imagine where 1 quart of oil would go in 200 miles and not be able to see it. This is what drove me to make a post for the first time in my life. Once again, all four cylinders tested out at

200 psi on the nose with proper needle climb. The best guess I?ve read so far is the idea of a leak that only presents itself when the crankcase pressure is up. I really need to go over this closer to look for clues. There certainly are no obvious ones. I have excellent eyesight and sense of smell, no blue smoke or odor. Thanks for the time you take to reply.

"Hachiroku_$B%O%A%m%/(B" wrote: > On Sun, 31 Dec

I agree, but that much oil blowing past the rings would show up in the exhaust stream, wouldn't it? A quart per 200 miles is a lot of oil to go missing without any trace.

And, I was addressing the point that the OP made that said his compression was . I was trying to say that what one looks for isn't the actual number, but that all readings be within a certain range. The alarm bels should start ringing when one cylinder is 200 and the next one is more than

220. Of course, the number is a real factor because if all are below the minimum, then that's a problem, but if all are above the min spec, but vary more than about 10%, then that's a problem too. One is a problem with the entire motor, the other is a problem with just one cylinder.

Back to the OP's problem, blowing or dripping a quart in 200 miles should not be hard to find. It should be visible on the ground, in the tailpipe, or in the coolant (which includes coolant in the crankcase). I set the coolant at the end because there should be temp control problems in this instance.

Allow me to ask the stupid question, how do you know it lost a quart? Has it lost a quart more than once, or did you have the oil changed, then check the oil after 200 miles and found some missing?

You're welcome. It's a weird problem. On one car, the sub-frame under the engine was showing oil, but on the other, there were no signs except for a low dipstick! But, I caught it early, having had it happen on the car I owned right before it!

If it goes on for a while, you should see oil SOMEWHERE, on the floor pan, the rear axle, somewhere! Have you gotten down on all fours and had a good look underneath?