Hot answers tagged compression
Wow! Textbook case of worn rings. The oil helps seal the ringland area. That's a large increase on cylinders 2, 3, and 4. Your fuel efficiency should be pretty poor with those compression numbers. Is it? If your fuel efficiency is miserable, it's time for a rebuild. Depending on the car it might be cheaper just to replace the engine with one from a engine ...
Measure each cylinder and buy over sized pistons / rings to accommodate the sizes.. this will be your cheapest option because installing new liners and buying stock pistons is very expensive / allot of machining work. If you don't have the time or money, keep driving it the way it is - if its not smoking bad you should get another 35k or more off of it.
Oil on the spark plug is likely either because the piston rings are not sealing or the valve guides are leaking oil. Both could also be related to low compression. You could either have ring seal problems or a valve that is not seating properly. Valve seat problems could be due to physical damage or carbon build-up coming loose. Guess at what is most likely ...
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