P0302 Misfire Cylinder 2
 

i have an 03 sedan. the computer read misfire on cylinder 2. the electrode was broke in the spark plug. i changed the spark plug and checked the compression and its 120. the boot was full of oil. i cleaned the boot.

also, i checked the coil and spark plug and is sparking. after that still reading misfire on cylinder 2. can a fuel problem cause this code?

That compression seems a little low have you checked another cylinder.

Isn't compression supposed to be around 180? or is it 160? somewhere in that area.

You could be leaking oil on to the spark plug. Sounds like your valve covers are leaking.

Few things coulda happened. Considering your electrode broke off, it could have scratched the cylinder wall, damaged a valve, head, or maybe your rings are worn. A leakdown is a more precise test. Do that and let us know the outcome.

and the oil on the plug, is it on the actual spark side of it that sits in the combustion chamber or where the coil plugs into?

i changed the coil order and moved the coil to cyl # 4. the computer said misfire on cyl 4. then i left the same coil but changed the boot with cyl number 2 and the computer said misfire cyl 2. i bought the boot that can be bough at a parts store (from $21 to $25) and the car worked just fine.

im just concerned the motor got damaged because of the broken electrode.

the oil on the spark plug of cyl 1 and 2 was on the coil plugs into. the coil, the boot and the spark plug were full of oil. the other spark plugs of the other cyl were clean.

leaking valve covers...sucks.

You need to replace those. Some people have had luck taking the VCs off and using RTV to seal up the gaskets.

A leak down/compression test of all 6 cylinders may be in order. Easiest way to test and see if there is any damage from the electrode.