HELP!! misfiring problem
07-06-2007, 08:43 AM
#1
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Location: Clifton, NJ
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HELP!! misfiring problem
About two weeks ago my z28 started to run sluggish and backfire/misfire when i got on it a little. Doesn't have to much power. I checked the battery and it said it was a bad battery. I replaced the battery and it ran good for 20 minutes and started doing it again. I then figured it was the alternator and replaced that last night. Once again it ran ok for 20 minutes and started misfiring again and running like crap. All the plugs and wires look fine, what else could it be? The car runs fine for the first 15 minutes, it seems like once its at running temperature it starts doing it mostly, and its not overheating or anything.
07-06-2007, 02:59 PM
#3
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i can tell you right now it would be worth it to check your distributor. optis are junk. theres no way around it unless you get a coil pack conversion(hard, expensive, not worth the trouble) or go with a better opti system.. MSD is about the best from what ive seen.. i went through 3 GM optis before i realized that.
07-06-2007, 07:17 PM
#4
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im throwing no codes, no check engine light, i work at a dealership and plugged it into the diagnostic computer and there were no codes everything matches up to what the book says it should. So im really confused now, The backfiring/misfiring only comes after 15-20 minutes of driving and comes and go when driving for a while. I think its running rich or something to because the exhaust also smells funny.
07-06-2007, 11:37 PM
#6
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When my Z28 had issues with miss firing and poor performance it ended up being the opti. It needs to be changed at 100k miles, as well as plugs and wires. After replacing them, car runs like it should no problems. Another thing you might consider is looking under the hood and check the intake elbow, inspect for tears.
Hope this helps.
Johnny
Hope this helps.
Johnny
07-07-2007, 08:30 AM
#7
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checked the intake elbow and its fine, plugs and wires look great and the kid i bought it off of told me he just did the plugs and wires a couple thousand miles ago.
Is there any way to check if the opti is good without replacing it? The thing that im confused about, and makes me think the problem is some sort of electrical, is that its an intermitten problem. It will misfire/backfire and run like total crap at times. Then other times it will run perfectly fine. Before I put the battery and alternator in, in was a continuous backfire.
Is there any way to check if the opti is good without replacing it? The thing that im confused about, and makes me think the problem is some sort of electrical, is that its an intermitten problem. It will misfire/backfire and run like total crap at times. Then other times it will run perfectly fine. Before I put the battery and alternator in, in was a continuous backfire.
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