help with misfires
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Joined: Nov 2002
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From: Los Angeles
help with misfires I have a 2002 GMC Yukon 5.3 with a Procharger. I'm running NGK TR6 plugs and Taylor wires. Recently, the truck has been throwing an SES light. I ATAPed it and it said that I was having a misfire in #7. I changed that plug and wires, but I'm still getting the SES light. What could be the problem? I'm not getting any white smoke out the back, so I don't think it's a blown gasket.
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From: toronto
Re: help with misfires What are your plugs gapped at ?
number 7 cylinder you say ?
I would do a compression test to rule out things
There has been a few guy with cylinder 7 as of late i hope it isn't that.
Do you have bigger injectors ?
Any tuning with the procharger ?
jim <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
number 7 cylinder you say ?
I would do a compression test to rule out things
There has been a few guy with cylinder 7 as of late i hope it isn't that.
Do you have bigger injectors ?
Any tuning with the procharger ?
jim <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
Thread Starter
TECH Regular
Joined: Nov 2002
Posts: 495
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From: Los Angeles
Re: help with misfires I'm praying to God that it isn't the dreaded "7TH CYLINDER SYNDROME," but I'll have to wait for the compression test to tell for sure.
My plugs are gapped at .035. Stock injectors with Ed Wright tuning.
If the cylider were blown, is there any way to tell, performance wise, smoke, rough idle, etc? It idles okay and there is no smoke!?!?!? Thanks for the info.
My plugs are gapped at .035. Stock injectors with Ed Wright tuning.
If the cylider were blown, is there any way to tell, performance wise, smoke, rough idle, etc? It idles okay and there is no smoke!?!?!? Thanks for the info.
Re: help with misfires if everything checks out that light wont go out until it cycles through or you have it cleared. Go to your local Auto Zone and they will clear it for free.
Thread Starter
TECH Regular
Joined: Nov 2002
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From: Los Angeles
Re: help with misfires I tried clearing it several times with ATAP, but it eventually comes back withing 20 mi of driving. I noticed that the light usually lights up during idle and low rpms. I put on the missfire counter with ATAP and it showed no missfires at higher rpms? Anyone know what this could mean?
