Oil burning

[TheSilentChamber]

I think your just imagining things.

[Fotheringay-Phipps]

I hope so.

I called up his mechanic who ran the test and spoke to him. He said the compression test showed compression of 140, which he said is normal, and that it's pretty evenly distributed. He said he could not rule out valve seal problems with this test, however.

I have a Haynes manual for the car (2000 Prizm/Corolla) and if I'm understanding it correctly it says the compression is 218, with a minimum of 145. Which is correct?

[TheSilentChamber]

140 sounds a little on the low end. is it smoking or is it just loosing oil? You are very good if you can notice the differnce in 1/10 of a quart... maby your just parked on a hill?

[Fotheringay-Phipps]

I've not mentioned noticing the difference of 1/10 of a quart. To clarify, it was low by 0.4 after one day and an ADDITIONAL 0.5 the next day, or about 1 quart in total. I've not been able to see any smoking. I will try to check again more closely, but there's certainly not anything easily noticable.

I got the actual receipt from the mechanic. He writes the following:

"Engine Compression test
All 4 cylanders have 140 PSI even, Dry
Wet test was 165 PSI
No oil found on the spark plugs."

Again this mechanic believes that these test results ruled out worn piston rings - he told me on the phone that if there is indeed oil burning it must be faulty valve guides. He said that 140 is an OK number and that in any event the more significant thing is that the cylinders did not vary by much.

I would have thought the indication is more like worn piston rings, based on the difference between the wet and dry pressures. But I am no mechanic.

I picked the car up from the dealer today, drove it about 50 miles, and lost about 1/5 of a quart, which is in line with my previous measurements.

So what's the assessment, based on losing a quart or so in 200-250 miles, dry/wet compression readings of 140/165, and no oil on the plugs? Taken all together, is it piston rings, valve guides or something else? And can anything be ruled out?

[bluevp00]

Take it to another mechanic (preferably a name brand franchise like Firestone, Midas, etc). Have them do the same thing - compression test/check plugs. AND have them also put it in writing. If the other mechanic says something different (that there is oil burning) then show it to the dealer and shove it in their face.

I don't think there's much you can do legally here but it might make your dealer have a change of mind and actually fess up to their lies. (assuming they were wrong)

[Fotheringay-Phipps]

Actually I'm on extremely solid ground legally, because (after disputing the credit card payment and threatening a lawsuit) the dealer signed an agreement to fix all issues with the car (there were others, of lesser import) "to [my] satisfaction" or refund my money. So if I don't think it is fixed then it's not to my satisfaction, and the deal is off. Theoretically I could weasel out of the whole thing in this manner, regardless. But I'd like to play straight, if the guy is making a good-faith effort to play straight with me.

So the question is really a matter of interpretation. Assuming the mechanic's numbers are accurate, is his interpretation accurate?

The dealer wasn't in when I picked up the car, but he had written on the mechanic's report that he would replace the valve seals if the car continued to burn oil. While I'm a bit tired of dealing with this car, if I believed the mechanic's assessment that any oil burning had to be the result of valve seals I would be inclined to just bring it back again and let him fix the seals. But if I think it is most likely - based on the evidence above - the piston rings, then I am just going to return the car and move on. So I need some educated opinions on this.

[CBFryman]

Originally Posted by bluevp00

Take it to another mechanic (preferably a name brand franchise like Firestone, Midas, etc). Have them do the same thing - compression test/check plugs. AND have them also put it in writing. If the other mechanic says something different (that there is oil burning) then show it to the dealer and shove it in their face.

I don't think there's much you can do legally here but it might make your dealer have a change of mind and actually fess up to their lies. (assuming they were wrong)

ive found that its better to take it to an independant mechanic that has a good reputation than to a midas or w/e. Just like its better to go to an indpendant parts store with a good reputation than to Napa or Autozone...or at least that is around here. Maybe its because i've know the daughter of pete oilin's autoparts for 6 years...i dont know