Questions and Answers
Laser Burning Oil
Q. I have a 1991 Plymouth Laser, 4 cyl, automatic 2.0 engine with fuel injection. It has 66,000 miles. Disc brakes, A/C, and cruise control.
My Laser just failed an emissions control test because of visible smoke coming from the exhaust at high acceleration, and I only have 2 choices, either get it fixed or get rid of the car. Since I want to keep the car for another 5 years, I plan to get it fixed.
I've taken the car to get evaluated and the best they could tell me was that it was an internal engine problem with oil being burned. The repair shop that I will be taking it to has said it sounds like either valves, rings, or head gasket has to be replaced. I realize that this is an expensive repair even at the minimum, but I believe I still prefer to get it fixed and keep this car which has run great for 10 yrs.
My question is, assuming that oil is leaking into the engine and is being burned, what in your opinion is the probable causes and repairs? Also, since I've always had regular maintenance on the car with oil changes every 3,000 miles, what would cause this problem to happen at 66,000 miles (even though it's 10 yrs old)?
Appreciate any information you can provide so I can be more informed when I take my car in.
Mike
A. First thing you have to determine is what is coming into the engine, coolant or oil. If the smoke is white and kind of sweet smelling, then it's coolant and is most likely a bad head gasket.
If the smoke has a definite blue color to it, then it's oil. If it is oil then a wet/dry compression will determine where it's coming from. First a dry test is done and the compression is noted. the compression should be about 160 to 180 pounds. More important than the actual reading is that they are fairly equal between all the cylinders.
One the dry readings are noted, then a couple of squirts of oil are shot into the cylinder. This has the effect of improving the ring seal. If the readings go up significantly, then you have worn rings and the engine needs an overhaul. If the readings only increase by a small amount, then it indicates the problem is with the valves, most likely the valve seals. If this is the case, replacing the seals is relatively easy and inexpensive.
With the smoke mainifesting itself under high acceleration, I would tend to believe the valve seals are the most likely problem.
