I have a 2002 tribute v6. The engine light came on and cylinder 5 was misfiring. I replaced plugs which were bad. I removed two plugs and there was oil on the threads of the plug and boot of the coil. After the truck plugs were replaced the truck still runs rough. Could it be the coil or could there be another engine, piston or gasket problem causing the oil to leak on the plugs and boots? Could the misfire cause this much oil to build up? Any other suggestions? I bought two coils to see if this helps and will replace them when they come in.

Thanks in advance,

Frank

 

I'd bet dollars to donuts that you've got a bad coil. Swap one to another position. If the misfire moves to the new position the coil is bad.

 

It is not unusual to find oil on the plugs and coil boot on cylinders 4,5,6 which are all in the front. The oil fill cap is just to the left and if you spill any oil it runs down into a recess by the plugs and coil and then goes to the lowest point, which is on your plugs and coil boots. Any that was left on the recess area gets burnt away or covered with dirt. Do not wash your engine off as water does the same thing and causes a arc and misfire. A lot of the auto parts stores now will pull the trouble codes for you for free. I would go and find out what trouble codes are coming up before buying any parts.