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what could be causing multiple misfire's?

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Old Sep 28, 2003 | 09:13 AM
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Default what could be causing multiple misfire's?

its only happening in bank 2 and its periodic, after the car is run and driven for a while, it appears, then dissapears about 10 min. later, I get around 300 misfires all on bank 2 within a 10 min. time frame, the plug wires seemed good, not sure about the coils, the injectors seemed good also, could it be one of those three things?, btw, how much are coil packs?, I still have the stock plug wires from 98, prolly should change um, if I swap the coil packs and plug wires from bank 1 to bank 2, and the misfire's are still on bank 2, what else could it be, someone said a bad o2 censor wouldnt cause this!, and I just felt for air leaking around the exhaust header flange and didnt feel any air coming out, help,
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Old Sep 28, 2003 | 09:27 AM
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Default Re: what could be causing multiple misfire's?

cam or bolt on car?


this is a hard one that i had on my car and never figured it out. i just deleted the misfire detection and the car ran alot better.
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Old Sep 28, 2003 | 09:32 AM
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Default Re: what could be causing multiple misfire's?

cam(207/217 .525/.525)for tha bottle, headers, ect.., stock heads, injectors,
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Old Sep 28, 2003 | 09:33 AM
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Default Re: what could be causing multiple misfire's?

I just cant figure out why it would come and go like it does, it also goes to +25 lean on bank 2 when the misfireing is present, car stumbles a little bit, can definatly feel it
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Old Sep 28, 2003 | 09:39 AM
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Default Re: what could be causing multiple misfire's?

mine was the same way, i dont think the ltrims went that far over.

did you check the o-rings on the intake ports? might be a vacume leak.

do you have efi live 6.0? if so you can do a cyl balance test to see for sure if its a true misfire.
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Old Sep 28, 2003 | 09:43 AM
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Default Re: what could be causing multiple misfire's?

are you talking about the o-rings that go between the intake and head?, 8 of them, I put brand new ones on when I put it back on, looked for other intake leaks,
Could this possibly be a cracked intake, somebody said if it wuz cracked this wouldnt happen, it would rev really high, I did split the #1 intake bolt a little when re tourkeing, but took it out quickly and put a washer
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Old Sep 28, 2003 | 10:22 AM
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Default Re: what could be causing multiple misfire's?

unplug your iac and see if the rpm's jump up. if so, its probably a leak.

try moving injectors around also.


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Old Sep 28, 2003 | 11:07 PM
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Default Re: what could be causing multiple misfire's?

Sounds like a vacuum leak.
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