I swapped out my ac delco for some Bosch P-2s, and i noticed oil on the delco plugs. After I put the new ones in, the car ran like a cylinder wasn't firing or the firing order wasn't correct ( got dark might have goofed ) What's going on? What is the source of the oil leak??

 

sounds like alot of oil is entering teh cumb. chambers through the valve guide seals or the rings. Oil and fauling makes an engine run like crap. I moved my old plugs over to my new engine and i didnt clean them, only gapped them and the motor had a few dead cyl. for a little while untill it cleaned the plugs off.

 

i got oil on my plug in cylinder 3...thankfully it's the only one, and im hoping its only valve seals, and not the rings. You could do a compression or leakdown test and see what that yields. Not too sure about what a compression test can *really* tell you, but i know that a leakdown test will help you determine exactly where the oil is getting in. Basically you pump air into the cylinder via an air compressor and proper adapter for the plug hole.... you then listen at different places for any whistling of the sort. Pull off the oil fill cap and listen, any noises suggests bad rings.... any noise around the exhaust or intake manifold suggests bad valves

...err, i hope im correct in what i just said....anyone w/ more knowledge please feel free to correct me

 

bak that isn't anything like a leak down test. a leak down test puts a set amount of air in a cylinder and after a period of time you see how much has leaked out, using 100 psi to start with makes the leakage rate easy to figure. is the oil on the eletrod or on the porcelin? if it's outside them it's a valve cover leak, inside might be valve seals, bad ring, dead plug wire, or weak spark.

 

sorry my bad...was reading a few pages the day before and that's what i read...ah well, at least now i know