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Are misfires normal???

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Old Apr 11, 2002 | 04:51 PM
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Default Re: Are misfires normal???

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ChrisB:
<strong>Do you have an aftermarket camshaft, and if so what are the specs?

Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No aftermarket cam here. Just bolt-ons.
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Old Apr 11, 2002 | 06:18 PM
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Default Re: Are misfires normal???

Do they stay around one cylinder in particular, or are they randomly distributed?

Are you still running stock spark-plugs?

Chris
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Old Apr 11, 2002 | 06:38 PM
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Default Re: Are misfires normal???

I never got any missfire codes until I put a T-1 cam in.I`ve got an SES light and A-Taped it and it shows no codes.But that was after I ran the car 3 on and off cycles and the light goes away.
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Old Apr 11, 2002 | 06:40 PM
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Default Re: Are misfires normal???

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ChrisB:
<strong>Do they stay around one cylinder in particular, or are they randomly distributed?

Are you still running stock spark-plugs?

Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">When I added headers at around 10,000 miles I added NGK 55's ...gapped to .5'

I now have 20K miles on the car. The misfires are randomly distributed.
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Old Apr 12, 2002 | 12:06 AM
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Default Are misfires normal???

My car is now finally in perfect tune. Perfect Ltrims (never above 0%) and perfect o2's (.88-.89) <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

However, I'm still getting misfires and was wondering if this is normal. I don't get any KR either.

Somehow atap is showing that I'm getting misfires in most of my cylinders!!! How could this be???

All I have are bolt ons for mods, and I'm maybe thinking injectors are bad, but I only have 20K miles on it. I am running 62psi fuel pressure which may add some load to the injectors. I dunno.

Any suggestions???

<small>[ April 11, 2002, 06:41 PM: Message edited by: verbs ]</small>
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Old Apr 12, 2002 | 12:48 AM
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Default Re: Are misfires normal???

Do you have an aftermarket camshaft, and if so what are the specs?

Chris
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Old Apr 12, 2002 | 09:22 AM
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Default Re: Are misfires normal???

do you get a lot or a little? Can you feel shake in the car at idle?
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Old Apr 12, 2002 | 10:48 AM
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Default Re: Are misfires normal???

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ragtop 99:
<strong>do you get a lot or a little? Can you feel shake in the car at idle?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Hell yeah I feel the car shake at idle....between my headers, true dual exhaust, no cats, and the exhaust dumping before the rear axle I get a decent amount of shaking....

I don't get a ton of misfires, at idle when I look at ATAP using the cylinder misfire history for each cylinder, I get up to 5 misfires in some of the cylinders in a minutes time or so...

the other wierd thing is when I'm recording atap runs, I have a category for total misfires. When I start recording, that number right off the bat will start at 8 or 12 or something high.

But as atap is logging more data while I'm driving, that total misfire number drops in 2's....to 6, then 4, then 2, etc...

<small>[ April 12, 2002, 12:42 PM: Message edited by: verbs ]</small>
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Old Apr 12, 2002 | 02:43 PM
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Default Re: Are misfires normal???

We're talking about the mis-fire current for each cyl, right?

This parameter records the number of "misses" out of the last 200. Anywhere up to 10-12 is very normal in my opinion. Try sorting your data by PRM and deleting anything below 1K rpm. What does it look like in other RPM ranges?

Mark
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Old Apr 13, 2002 | 12:14 AM
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Default Re: Are misfires normal???

I get random misfires too. But I think its my TR 6 plugs. Not sure tho. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
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