Ok my 283K 05 has been running like a cammed hotrod and gas mileage has been down to 35mpg exhaust is lopey. for a long time. I found oil in the #2 cylinder replaced the valve cover gasket and all of the plugs no change. finally through a misfire cylinder 2 code on Friday. pulled the spark plug on cylinder 2 there was oil on the threads. took out my camera scope and put it in the hole and sure enough there was oil in the galley. (not in or n piston it looked fine. inspected cylinder 3 and no oil. cleaned up the plug checked the gap and went for a test drive. went about 10 miles and misfire on 2 came back. cleared it. drove 1 mile and now cylinder 4 is misfiring and she's a bouncing. its frigging torrential downpour here and I don't have a garage. so I'm looking for any ideas to troubleshoot this thing. there is also what I would consider lots of valve train "chatter" I thought of replacing the head with a low mile used one for 100$. I need to do a compression test. I know that. Help! Thanks Don
You could try switching the coils and plug to different cylinders and see if the misfire follows after the change. If you remove the coils inspect them for carbon tracking. Part 3 -Carbon Tracks are a Common Cause of Ignition Misfires
that's one thing I didn't do. I didn't because of the oil all over the boot, ceramic and threads and the inside of the coil had oil in it to. so I ruled out the coil pack. like I said misfire is now on cylinder 4.
oil in the hole where the spark plug is threaded in. so its exposed to coil and ceramic of plug. its an industry term I made up.
Spark plug well. If you have oil in there you did not replace the v cover gasket properly. If leaking a lot of oil you may have damaged a cop (coil on plug) it may have shorted out from being soaked in used oil. Fix the gasket so it does not leak oil. Answer this question. Have you ever ran the engine so low on oil it threw a master caution red icon on th dash?
Engine overheat. Probably warped the aluminum head. The head warps pretty easy on a overheat. Really bad design you lose the belt you lose the water pump and no engine temp meter on the dash. By the time you see the overheat icon on the dash engine damage has ensued.
I guess that I will bang that out. its the least expense 100$ for used head with warranty locally and I have had this thing apart so many times I can do it blind folded.
I am newbie and really know nothing about car, my 07 Prius, 200+K miles, I ran into this situation, I changed motor oilsbut spilled due to too dark, 4 days late, it had P0302, misfire, motor oils inside all spark plugs/coilpaks, I clean all motor oils with clothes, and water, It ran fine for 2 days, pouring rains, it misfired PO301, I cleaned all coilpaks , it was still misfired, I noticed that coilpaks/rubber with brown motor oil stains, I guessed that those motor oils stains reacted to water = carbon = conductive, I sanded those motor oil stains on coilpaks and rubbers, car run well without misfire.
