Thread: p301 misfire '02 Grand Prix SE

This is the code pulled at O'Reily today. The car was running fine yesterday. Got in and started up and it was putting with ses blinking. I thought someone put a banana in my tailpipe or stole my new california cat(installed by shop). No banana and cat was still there.

I am having the hardest time looking at the plugs, I see the three on the front or the green outside, I havn't taken a look yet, but omg the ones on the back are hard to find or are they? Anyone with similar problems in the past? The cat is new, I was thinking it may be the fuel injector. I know I need to check the plugs. What is the best way to get at the back plugs? Do I just tug on the green part at the end of the wire going to the plug? I don't want to ruin anything.

The ses is on all the time and blinking when driving, I drove about 3 miles today with this going on. Yesterday it was doing just fine, no lights, nothing. Hmmmmm.

P0301 = misfire on 1 and 1 appears to be the far one on the back passenger side.

I'd take a look at the plug and the wire.

If you have no luck with that, try moving that coil, and that injector.

What does moving entail? I noticed the number 1 on the coil leading to the rear plug. I do have some good news, I took off the wire to look at it from the coil, not the spark plug, looked good, I reconnected and car is now fine. This was after I thought number 1 was on the front and didn't notice the numbers on the other end. Am right when saying the other end is the coils? They sit on top of the engine and are where the wires connect? Anyhow, I brushed the front plugs and the wires on the front don't look so good on the inside, tried brushing them and getting dust out. I also tried removing the front left spark plug thinking it was number 1, couldn't get it to budge, so I imagine there is no way I will be getting anywhere with the back spark plug. I have an extension, but the handle piece I have is not the best, can't seem to get any leverage because of the space. My mechanic charges $16 a plug + 15% to use customer parts, I bought bosch(no gapping required) plugs and was thinking it would be best to just have the mechanic do it. I am sure I can do the wires the following morning when the engine is cold. The car is running fine now, I cleared the code, but I know the wires and the plugs, at least the front three look dirty are starting show wear, the wires just look bad and show corrosion.

Have you or has anyone replaced a fuel injector on this car or one like a 2002 Pontiac Grand Prix SE 3.1? The mechanic also suggested I put Heet in the gas tank and try that as well so I did. Only drove another 5 miles.

well if that solved your issue i'd suggest running some seafoam through the gas tank (think of it as part of a tune up) and getting new wires and plugs.

If you wanted to pay your mechanic to do it I'd suggest AC delco plugs since you're stock and they're a good plug.