PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

missfire for what????

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Old Mar 6, 2005 | 05:35 AM
  #1  
akaceril's Avatar
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From: Tacoma, WA
Default missfire for what????

got a problem fellas.....
Friday I did a compression test and a leakdown test on my 2000 SS( all numbers were good by the way ) put the car back together and then a miss . only under load, can't even tell at idle or cruise. Felt like a broken valve spring at first. I pulled the valve covers and nothing there . Pulled the plugs and my wires(MSD) and ohmed them out, all look normal . I also re-gapped the plugs(NGK TR-6) just to check . can't remember how to check for a bad coil. anyone know??? other than that everything else is good. Anyone got any ideas.

Oh when I pulled the valve covers, I also checked the rockers and pushrod's and the car is tunned by MTI I had them program out missfires, cause of my cam(224/224 .581/.581 112LSA) so the HP tunners program can't read any codes. Before you say, it the program is my friends and I can only scan my car with it for he has a 98 model cable.
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Old Mar 6, 2005 | 03:06 PM
  #2  
jimmyblue's Avatar
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From: East Central Florida
Default

Hook up the HPTuners and just scan the Misfires-Current #1-#8
along with however many of the other "usual suspects" for fuel
and spark tuning as will fit in the PID list. A single cylinder problem
will show up pretty obvious. The current misfires are still "live"
even though code reporting is suppressed.



Originally Posted by akaceril
got a problem fellas.....
Friday I did a compression test and a leakdown test on my 2000 SS( all numbers were good by the way ) put the car back together and then a miss . only under load, can't even tell at idle or cruise. Felt like a broken valve spring at first. I pulled the valve covers and nothing there . Pulled the plugs and my wires(MSD) and ohmed them out, all look normal . I also re-gapped the plugs(NGK TR-6) just to check . can't remember how to check for a bad coil. anyone know??? other than that everything else is good. Anyone got any ideas.

Oh when I pulled the valve covers, I also checked the rockers and pushrod's and the car is tunned by MTI I had them program out missfires, cause of my cam(224/224 .581/.581 112LSA) so the HP tunners program can't read any codes. Before you say, it the program is my friends and I can only scan my car with it for he has a 98 model cable.
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Old Mar 6, 2005 | 07:42 PM
  #3  
Old Drive-ability's Avatar
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Default

If it didn't miss before you did your thing you likely cracked a plug or damaged a plug boot. A little hole will cause the engine to miss more when its lugging in drive with the tcc engaged. Often it wont miss under wot because the mixture is rich and more conductive.
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