Electrical problem?

Hey, i posted like two weeks ago about my car backfiring and sputtering and all that blah blah blah. They thought they had the problems fixed when they replaced the spark plugs, and a fuel injector. But, guess what, the problem is still there. The mechanic has had my car for two weeks, and has ran compression checks on the motor, scans on the computer, but two cylinders are misfiring at the same time still. He has determined the problem is probably electrical, but can't pinpoint it... Does anybody have any idea of where this problem might be found, so I can forward the information on to him, to get my car back? Anything at all that might possibly help will be SO greatly appreciated!!

Dont know what year car you have, but I would replace the wires. If it has a coil pack I would check that and replace if necessary. If it has a distibutor, replace the cap and rotor. Beyond that if it still does that, you will need to check the timing. It could have jumped time. Four cylenders have a belt for timing that should be replace every 100K or so.

My friend has a 92 cavalier with the 2.2L engine. He had misfires on half of the cylinders, and the solution was the computer that controls the fuel injection. Hope this helps

Oh, sorry, my cavy is a '98 z24 with about 96,000 miles on it

I just had this same problem on my 2.4 L after I tested my injectors. The problem was I switched two of the injector plugs. I started misfiring through the intake. Check your wiring for where two wires come out of the harness at the same point and switch them.

This is going to sound silly if you already checked, but could two of the plug wires possibly gotten switched?

ok, here's my input. I have a 98 z-24 myself. I know these motors pretty well. If you are backfiring through the intake there's a good chance that OVERTIME is right. If by some chance he is not you need to do two things.
#1. Carefully remove your cam cover From your car. Your car is equipped with DIS (distributor-less ignition system) mean that you have a coil pack and your spark plugs are housed down in the motor. Ok, you need to get a good flashlight and look down in the holes where your coil contacts rest when the cover is on. You are looking to see if those springs which are your spark plug connectors are bent or stuck down in the housing or just generally obstructed.
#2. If all from #1 looks good then you need to see if there are any visible defects on your Ignition Control Module assembly. Visible defects being fingerprints on or near those 4 silver nipples that are pointing down. Also check to make sure that there is a bonding strap in place beneath one of the mounting bolt grommets. The bonding strap should be routed underneath the Ignition Coil Housing Assembly. Either one of those can cause a backfire, among many other things, but we'll stay basic for now....please keep me updated on this...

Alright, I showed everybody's posts to my wonderful mechanic... he said "well, this would've helped about a week ago, but we've already done/checked everything that has been suggested" but he did ask me to inquire if anybody has more ideas... we are all at a loss for intelligence on this matter right now. I might even have to sell my beautiful cavy :( so if anybody can offer more help i'll be more than appreciative!

Man I'll tell you what, if you like I'd be willing to come take a look at your car...if you name the place and time. My dad is the number one mechanic in the state of kentucky. I'll come check it out and relay to him what I'm seeing and I'm willing to bet that within a day or two we can find the problem and maybe even get it fixed....I don't wanna see anyone sell their car because of some messed up problem

...but two cylinders are misfiring at the same time still...



#2. If all from #1 looks good then you need to see if there are any visible defects on your Ignition Control Module assembly.


If I had to hazard a guess on what would likely fix this problem, I would say the ICM or the wiring harness from the ICM to the coils. This module controls when the spark is sent and to which cylinder. :2cents:

Haha, thanks for the extra help!! My mechanic got it running like the chevy it is. AFTER replacing three spark plugs, the ignition coil (?), some tower thing *lol*, and the cam sensor. Thank you guys so much for helpin, all of it did give him some help, he had just been ahead of my relay of messages!

no problem at all...Damn glad to hear you got it up and running....that is awesome