Well my check engine light came on in my 01 disco w/ 82k miles. When we ran the codes it said it was the passenger side O2 sensor. I let it go and then driving home one night it started to run rough and then the check engine light started flashing. But once on the highway at 60mph+ it was fine, only at lower speeds it ran rough. So we ran the codes again and it threw up like 15 different codes so my mechanic erased them and then took it out for a drive then the check engine light came back on so he checked it again and it says cylinder 3 miss fire. that was about a week ago since he hasnt had time to get to it yet and my wife has to drive it to work. She said it still runs rough and studders but doesnt act like it will die or anything like that. my question is what do you guys think this could be since now the O2 sensor code is not back up and now its a miss fire in cylinder 3. If i could fix it before my mechanic can get to it that would be great, so looking for some input from you guys. Where would you start at as far as trying to trace the problem?

Thanks

David

 

Magnecor 8MM wires and Bosch +4 plugs.

What grade of fuel are you running?

 

mid grade and premium. mostly amaco (89, 92)

 

Best case,, just plugs and wires.

Worst case,, stuck valve from mid grade gas,, valve job.

 

If you want some good feed back, don't ask what we think, give use the exact fault codes so we have something to work with.
If you don't have them, go get them read again and get back to us with each 4 digit fault code number.

 

Only use premuim

 

the code that he gave me is P0303 cylinder #3 missfire

thanks again

 

Is that now the only code, what happened with all the others?

 

that is the only code as of right now... when it came in w/ all those codes he just cleared them and then drove it and when the check engine light came back on and he scanned it that was the only code that popped up...

 

any input on where to start w/ that being the only code? plug and wire on only cylinder 3? what type of plug and wire if that is the case? she told me today after filling it up and running a tank of good premium gas along w/ the fuel cleaner it started to run better