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what should normal misfires be with cam?

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Old 08-23-2002, 04:12 PM
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Default what should normal misfires be with cam?

under the current misfire history

i get anywhere from 8-33 on every cylinder off and on at idle

i just replaced my broken 918 and was logging things at idle. The cyl it broke on was showing the same as the rest bascially. One minute it shows 12misfires, the next time around its 28

but i htink this is normal for any cam at idle right??

I have TR-6's with a 224 .563 114 cam
Old 08-23-2002, 11:05 PM
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Default Re: what should normal misfires be with cam?

Yep...normal. I quit logging misfires.
Later.
Old 08-24-2002, 09:21 AM
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Default Re: what should normal misfires be with cam?

I find similar missfire count with my setup, you could probably help this with more timing at idle, if you have LS1edit.Worth a shot, but if not only precaution to be taken with motor that has constant idle missfires is to change oil slightly more often.
Old 08-24-2002, 10:05 AM
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Default Re: what should normal misfires be with cam?

Your pcm looks for misfires with the camshaft & crankshaft sensors. It watches each cylinder firing event and anticipates each accelleration of the crank by a cyl. firing. If pcm sees crank decel on any firing event it logs it as a misfire. A nice cam with a good lope will put pcm misfire detect on overtime don't worry about it. Misfire logs are meant for regular every day vehicle's for diagnostics.
Old 08-24-2002, 11:04 AM
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Default Re: what should normal misfires be with cam?

I would think you shouldn't have misfires with that Cam.I have no misfires with TR's 220 on 114 Setup.
Old 08-24-2002, 04:55 PM
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Default Re: what should normal misfires be with cam?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris ARE 360:
<strong>Slowhawk you are a M6 with a higher stock idle. He is an A4.
Cheers,
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">OOPS <img border="0" alt="[kaboom]" title="" src="graemlins/gr_bomb.gif" />
Old 08-24-2002, 10:46 PM
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Default Re: what should normal misfires be with cam?

yep, i have the sucky cam modded A4 <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

but i checked after i went and most of them went away under normal driving.. maybe 1-2 here and there but nothing extreme. They went away as my rpms starting going up so i guess she's normal <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

thanks everyone!
Old 08-25-2002, 12:37 AM
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Default Re: what should normal misfires be with cam?

Slowhawk you are a M6 with a higher stock idle. He is an A4.
Cheers,
Chris
Old 08-26-2002, 06:37 AM
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Default Re: what should normal misfires be with cam?

I get some very small misfires at idle with my b1 cam in my m6..they go to zero as you step on the gas..so misfire is still good to check for wire and other problems ,I don't even throw the random misfire code much..and if you get really bad misfiring the engine can set codes for individual cylinders it looks like from looking at the code lists.
Old 08-26-2002, 08:02 AM
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Default Re: what should normal misfires be with cam?

HD: What is your idle speed? If you are around 900, the misfires should be minimal. They should go away completely at 1000 - 1100 rpm with your cam.

BTW, if the misfires are concentrated on a couple cylinders, such as ones that had the springs break, you may have real issues. If they are random through most of the cylinders, you're probably OK.

<small>[ August 26, 2002, 08:04 AM: Message edited by: Ragtop 99 ]</small>
Old 08-26-2002, 08:03 PM
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Default Re: what should normal misfires be with cam?

</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>HD: What is your idle speed? If you are around 900, the misfires should be minimal. They should go away completely at 1000 - 1100 rpm with your cam.

BTW, if the misfires are concentrated on a couple cylinders, such as ones that had the springs break, you may have real issues. If they are random through most of the cylinders, you're probably OK.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Joel, im around 850 idle. When i get up to 1200 i dont think i have any.

But also i made sure to check i didnt have them around the 4cyl(broken spring)
atfirst i was freaking out cause it was showing 28 or so misfires there off and on. Then cyl 3 had them and they rambled around. I noticed after i got back from driving my misfires at idle came down to like 0-12. I didnt even have any 20's showing




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