Yesterday while driving for about an hour, suddenly the car ran a bit rough and the SES light came on. I checked it when I got home and found a misfire in the #2 cylinder (P0302 code). I drove it last night with the misfire for a 45 min round trip. It seemed to be neither better or worse.
When I pulled the coil this morning, there was oil a couple inches up the coil in the spark plug well. I've tried to look this up here and w/google, but the answers seem to be for oil on the threads and on the spark end of the plug, not for where the coil meets the plug. I did try to pull the plug, but it was stubborn and I didn't want to break it off. Maybe I'll use the impact wrench later, but in the mean time, I'm looking for ideas as to how bad this is. I'd like to think it's a valve cover gasket, but my gut tells me otherwise. Any thoughts as to what I'm dealing with?
Most likely valve cover gasket. Common failure item. Replace it first and see where that gets you. Also DON'T use an impact wrench on the plug; you will break it.
That's probably not true. Take a look at the 3V Triton heads, impacts are one way you avoid snapping the two-piece plug apart. If you go to town on a non-impact tool you're just going to mangle the threads.
If the plug is stuck heat up the engine. Aluminum (like the head) will expand more than steel (like the spark plug threads) and you'll have a much easier time removing the plugs.
Yes. VCG. No other reason really. The gasket stats life rubbery and goes hard and no longer presents a barrier to the oil. Same wih the oil filter housing gasket. Rubber gaskets SUCK.
PS: And it sounds pretty bad too. Get it done. Pronto.
Easy DIY, one tip, use high quality rtv in the corners and give it a few minutes to set up BEFORE placing the valve cover back on the car, then, wait overnight before starting it to let the RTV fully cure. This is extra insurance against leaks.
I did try to pull the plug, but it was stubborn and I didn't want to break it off. Maybe I'll use the impact wrench later, but in the mean time, I'm looking for ideas as to how bad this is.
Valve cover gasket & you can also get some rain water in there if the vanity cover isn***8217;t on too. If you can***8217;t get the plug out, get the engine a little warm first
Thanks again everyone. Gasket is on, no more oil in in the plug socket, but still misfiring on cylinder #2 with the P0302 and an additional code of P1250. Between work and being away for the weekend, I haven't gotten a chance to check it out. I'm guessing that the plug is fouled and/or I damaged the vacuum hose that goes around the back of the VCG or maybe loosened an O2 sensor connection. Sometime this week I'll get to it.
Oil in the spark plug well will affect the coil before affecting the spark plug. Oil isn't going to seep past the threads to foul it.
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