misfiring need help please??

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Oct 4, 2006 | 09:11 PM

Streetracer361

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misfiring need help please??

Here is the story, my car has a misfire (not throwing code). It misfires when the car is idling but when I take it to 1000 rpms it does not misfire. I have a 224/224/581/581-112. I also have msd wires and ngk tr55's. I dont know if it matters or not but I do not have cats. Can't find out whats wrong, I need some help on trying to fix this problem.

Oct 4, 2006 | 09:33 PM

Joey7489

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do you have headers?.. if you do, wait until night, turn the lights off and start the car with the hood open. watch for sparks in the engine bay. my headers ate right through my MSD 8.5's

Oct 4, 2006 | 09:43 PM

2001NBMZ28

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From: Jacksonville, FL

I agree, easy to check too - friend of mine had a plug wire arcing on #6.

Oct 5, 2006 | 04:20 PM

Streetracer361

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Yes, I tryed that, I had one wire that was arcing of the header but I replace it. I dont know if it is in the tune or what. I don't know if it matters, but I am checking it with a snapon scaner. I think that the MSD wires are just crapy wires.

Oct 5, 2006 | 08:32 PM

Streetracer361

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can anyone help me find my problum????

Oct 5, 2006 | 08:40 PM

oange ss

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From: Texas

need to tune idle misfire table to compensate for the cam

Oct 6, 2006 | 09:43 AM

Streetracer361

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It has been tune from MTI, but I think it needs to be tuned agian. Is their anyone that could help me with a tune I south texas???

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Oct 7, 2006 | 12:34 PM

2xLS1

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From: Warr Acres, OK

Anytime you install a cam that has some lope to it, the PCM will see that as having misfires. The stock misfire tables are set up for the crankshaft movements expected with a stock cam. The PCM is looking at the acceleration events of the crank position reluctor ring as measured by the CPS. The misfire tables in the PCM need to be changed.

Oct 8, 2006 | 11:32 AM

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Streetracer361

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thanks for the help. How would I fix that, and is their anyone in South Texas around the SA area that is good and cheap on their tunes?

Oct 15, 2006 | 06:39 PM

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ChevyGoldfinger

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Quote:

Originally Posted by Streetracer361

thanks for the help. How would I fix that, and is their anyone in South Texas around the SA area that is good and cheap on their tunes?

Good and Cheap usually don't go together.

You almost always get just about what you pay for.

Oct 16, 2006 | 10:28 AM

#12

Streetracer361

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I had the car tuned at MTI but it was a crappy tune. Its too far for me to go back so I was looking for someone closer to SA. If you know anyone, let me know thanks.