Apparent oil abduction by UFO

I have a 99 Honda Accord. I’ve had it since new and had all recommended maintenance done on time, including oil changes every 3700 mi. No problems until an accident a year ago. Four days after getting it back from the repair shop, I had to add 3 quarts of oil (no warning light on, no oil on the ground, no black exhaust).

The repair shop says it has nothing to do with their repairs on hood, coolant system, air conditioning.

The dealer says no visible oil leaks, no oil in exhaust pipe, no cross-contamination with coolant, compression test fine. We changed to 10/30 weight oil (normally 5/30 I think) to see if it helped, but the abduction rate seems to have increased (was 1100mi/qt, now 800mi/qt).

The smog check guy says perhaps the O2 sensor is malfunctioning (never replaced in life of car).

Please help…

[b]It’s not the O2 sensor. If it were a problem with the O2 sensor, the Check Engine light would be on.

I think the engine is burning the oil, and you can’t see it yet because the burning rate isn’t enough to overwhelm the catalytic converter.

Also, if a vehicle takes a hard enough frontal impact while the engine is running, it can damage internal engine components such as rings, pistons, and cylinders.


I agree. If it isn’t leaking, it’s burning.

Thank you–amazing response time.
How do I get this diagnosed/repaired?

Let’s see; crash damage and now it’s become an oil burner. I’d start shopping for another car.

If it weren’t for the crash damage I might think about fixing the engine, but this car has two strikes against it.

The other option is to keep pouring oil into the engine and drive it as long as you can. Sooner or later, however, the catalytic converter will be ruined.

Has anyone suggested replacing the PCV valve?

Using (burning) oil is usually caused by worn piston rings and cylinder walls. Checks of the engine vacuum and cylinder compression are used to determine how much wear (approximately) has taken place. The “fix” is to rebuild the engine. Alternatively, one could just run it until it wouldn’t run anymore, which might be years from now with regular spark plug changes.

How big was the crash?

I agree with McP. Start shopping. While it may not have been cauised by the work they did, clearly something was damaged.

Another option you have is to file a supplemental claim with the insurance company. Additional damages discovered after repair are still covered by the claim. The trick will be determining exactly where the oil is going.

  • mountainbike

Thank you again for the responses!

mcparadise: The car passed its smog test this month, but the hydrocarbon measurement was 55ppm (max allowed is 56 and average for passing cars is 9). Is this an indication of burning oil? Also, no repair place has mentioned a PCV valve. What is it?

anonymous/mountainbike: The accident was not high-speed or high-impact, but it may have been hit in an unusual way. The damage was on the right front, but the air bag did not deploy. I was told that the car was hit between the sensors…In any case, I haven’t settled with the insurance company yet because of the oil leak.

hellokit: The car showed no problem when it had a compression test. Is that relevant to piston ring/cylinder wall wear?