Hi, I have a 96 Z24 with 2.4. 150,000 miles on the car runs good until recently. It's been down on power with the engine light coming on and off intermittently mostly during city traffic it would light up when idling around town. Hwy driving the car would run better and the light generally would go out. I replaced the coil housing because it was cracked and the plug boots recently and the car was running better. Well, after a few hundred miles of better performance, the car just really started acting up again. This time, a very noticeable mis-fire. The check engine light is now blinking!! I had a scanner put on it and the code is P0300 "Engine mis-fire detected by PCM" well, duh, I knew that. What is the process of elimination / tests I should perform to nail this thing down and not just throw a bunch of money at it replacing parts??? I had the ICM checked at Autozone (actually, I bought one and the problem didn't go away so I took it back) I did put two new coils on it but probably didn't need those either. Thank you all for your advice!
have you tried a fuel filter or injector cleaner?? anything that can cause it to misfire will cause it to misfire. Also check the 8 wires that plug into the IDI cover and ensure that none of them are worn threw or shorting out.
You didn't mention spark plugs.. when is the last time you changed them? did the issue start after you installed anything?? try undoing that change.
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I put a new fuel filter on it today and added some injector cleaner in the tank. No difference. Car still has a dead cylinder. The exhuast is popping a bit so I'm guessing it raw fuel in the Cat. Plugs are only a few thousand miles old. Guess I'll be taking it to the shop.....
You have one dead cylinder or two? What do the plugs look like? (Any mechanical damage?) How about a compression test?
Subscribed. Today my van just throw P300......damn. two cars need to work on
If all the plugs are firing, then you likely have a dead injector. With the engine running, disconnect one injector at a time, the one that you disconnect that has no effect on the engine RPM is the dead one.
Well, I finally got the car fixed. Apparently the POS coil housing cover I bought from Autozone was defective. I replaced it with a GM piece and all is better now. I hate it when you replace an old part with a defective new one. Really screws with you.....
Anyway, thanks for everybody's input and advice!!
