Misfire Help
06-18-2008, 06:27 PM
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Misfire Help
Alright so i threw the P0300 code the other day, so i changed the plugs and tried again. then my interceptor said from 8- 22 misfires at any moment. i checked the gap and everything and it appears fine, and the new plugs are fine. its mostly misfing in cylinder 1. i need help
06-18-2008, 06:31 PM
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06-18-2008, 06:36 PM
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The problem with the cobalts ignition system is that the best way to diagnose a problem is to install a known good part. If you have aftermarket plugs in you car get rid of them. Improper plug resistance causes coil and module failures. Your looking at a new coil cassette or control module and the only way to figure out which is to either have a GM tech diagnose the problem or plug in a known good part. Best of luck
06-18-2008, 09:14 PM
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ok guys...here is whats up...he has checked his plugs, re-gapped...no fouling...he was getting a misfire on cylinder one, then he swapped injector with injector two. the misfire followed to cylinder two...
the misfire is only at idle and low rpm...and since he just put in some flow matched 60#'ers, im guessing there is an issue with that injector and it is running a hair lean at such low idc's....anyone got any other ideas?
the misfire is only at idle and low rpm...and since he just put in some flow matched 60#'ers, im guessing there is an issue with that injector and it is running a hair lean at such low idc's....anyone got any other ideas?
06-18-2008, 10:20 PM
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Trust me, you are not alone on this. I know of at least 15+ other people with this same problem. Its a Cobalt thing. Lol
If anything, the car is running to RICH at idle, not too lean. I will be able to let you know soon, we are hooking my buddies Wideband back up to my car. I will keep you posted.
If anything, the car is running to RICH at idle, not too lean. I will be able to let you know soon, we are hooking my buddies Wideband back up to my car. I will keep you posted.
06-18-2008, 10:48 PM
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Trust me, you are not alone on this. I know of at least 15+ other people with this same problem. Its a Cobalt thing. Lol
If anything, the car is running to RICH at idle, not too lean. I will be able to let you know soon, we are hooking my buddies Wideband back up to my car. I will keep you posted.
If anything, the car is running to RICH at idle, not too lean. I will be able to let you know soon, we are hooking my buddies Wideband back up to my car. I will keep you posted.
06-18-2008, 10:53 PM
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06-18-2008, 10:58 PM
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well i just put 2 more brand new plugs in 2day and i have no friends with 60's around here
06-18-2008, 10:59 PM
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06-18-2008, 11:01 PM
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06-18-2008, 11:02 PM
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i have the same problem but my car misfires every time at like 3500 rpm..it just sputters, but if i keep my foot down then it feels shitty but does go more!! but i alos got the p0300 at idle twice, and i knew this already so it didnt really matter...im gunna change the tune, and put in new coil packs...anything else u guys recommend?
06-18-2008, 11:04 PM
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Oh. well try to find someone some what close to you and see if yall can meet half way to switch for like 10 minutes and see if that is the problem.. thats my best guess instead of buying another harness when that might not be the case
06-18-2008, 11:04 PM
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i have the same problem but my car misfires every time at like 3500 rpm..it just sputters, but if i keep my foot down then it feels shitty but does go more!! but i alos got the p0300 at idle twice, and i knew this already so it didnt really matter...im gunna change the tune, and put in new coil packs...anything else u guys recommend?
06-18-2008, 11:05 PM
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i have the same problem but my car misfires every time at like 3500 rpm..it just sputters, but if i keep my foot down then it feels shitty but does go more!! but i alos got the p0300 at idle twice, and i knew this already so it didnt really matter...im gunna change the tune, and put in new coil packs...anything else u guys recommend?
06-18-2008, 11:10 PM
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06-18-2008, 11:11 PM
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cuz i heard the coilpacks can go bad, and i might replace my Crankshaft positioning sensor..wut yali think??
06-18-2008, 11:12 PM
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06-18-2008, 11:12 PM
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