98 cavalier z24 PO302

My son's z24 recently started skipping at times. Installed new plugs about 4 months ago. They look fine. Pulled code PO302 (Cylinder 2 misfire). I switched plugs in 2 and 3. PO 302 returned a week later. I installed new plug boots and thought problem was fixed but came back about a week later worse than before. I believe next step would be to replace coil housing. Do these frequently go bad? Is there something else you guys would recommend checking or trying before putting in shop?

thanks david holley

Reply to
dlholley
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i don't know if it could be this, but just for the heck of it, check the fuel pump pressure. if its down even a little, then you will have problems.

Reply to
hubcit

If I remember right, GM's of that era had problems with the fuel injectors getting dirty, causing single cylinder or multiple cylinder misfires. There was a GM TSB on this problem that I saw a long time ago, I don't know if it covered thru 1998 models or not, but I've personally seen several cars with the problem.

I'd try some fuel injector cleaner for the next 2-3 tanks and see if it clears up.

Chris

Reply to
Hal

I have switched plugs 1 and 2 now and cleaned coil housing and re- applied boot grease to the plugs and the problem has gone away for now. What holds the coils in place inside the housing? There doesn't appear to be anything holding them, but they were stuck and I didn't want to take a chance on damaging the housing. We have ran a can of seafoam in the gas. Will try more. Any other brands you would recommend? thanks for your response. david

Reply to
dlholley

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