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Random/Multiple missfire, Need Help!!

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Old Feb 9, 2009 | 06:28 PM
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Default Random/Multiple missfire, Need Help!!

It's been acting up for a while now but only when the motor is cold. I have tried plugs, wires, 02 sensors/simulators and a few of the other obvious things and it still throws the Random/ multiple miss fire code along with an EGR code (EGR is removed). It doesn't throw the code very often and the SES light stays off most of the time.

The car is a cam only set up w/ a 6spd and the best trap Ive got was only 114. Only has 61k so I doubt its a fuel pump issue or failed coil pack etc.

It was tuned by the previous owner on ls1 edit and pretty much all he did was richen it up from 2400rpm up. He also left one of the EGR codes in there.

The car doesn't hold a strong idle upon first start up, even when its still a little warm. When I start it up for the first time of the day it will run like crap until I get to the end of the street then after it warms up a little it seems fine.

I'm beginning to think it has something to do with the tune or it's a failing censor (CPS etc) but just wanted to see what yall thought before I spend more money. Any help is much appreciated.

And I have done many searches on this subject but can't narrow it down.
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Old Feb 10, 2009 | 05:37 AM
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Sounds like it just needs a real tune!
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Old Feb 10, 2009 | 05:54 AM
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yep, get a real tune
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Old Feb 10, 2009 | 09:05 PM
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Thanks for the replies, although its not really what I wanted to hear just because of the cost associated with a good tune.

Im gonna check the fuel pressure when I fire it up in the morning just to make sure its not the fuel pump.

Anyone else have any suggestions? Also where could I get a good tune at a good price around Austin/San Antonio?
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Old Feb 11, 2009 | 12:12 PM
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Fired up with right at about 60 psi fuel pressure this morning.

Forgot to mention that it is worse when I have the a/c on, I geuss that would also point to the tune being off.
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Old Feb 11, 2009 | 12:41 PM
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sorry to say you don't need a budget tune. you need a good tune from an experienced tuner - possibly to correct for whatever the previous owner did just to get the car to run.

you should check the regional section for a good tuner in your area.
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Old Feb 11, 2009 | 12:55 PM
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I've checked, most of the closer sponsors are in Houston. I do have one shop in mind that is just north of San Antonio but they are a non sponsor.
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Old Feb 11, 2009 | 12:56 PM
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if you have a local forum get on there and see if they know any one that will tune it
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Old Feb 12, 2009 | 06:58 AM
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[QUOTE=stoverz28;11028076]Thanks for the replies, although its not really what I wanted to hear just because of the cost associated with a good tune.


I have stated many times, it seems like no one ever includes the price of a tune in their build up budget, Tuning is as critical as selecting the parts for a proper combo. I just don't get it where people will spend thousands of dollars on parts then do not want to spend the $300-$500 for a tune...
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Old Feb 12, 2009 | 01:55 PM
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^^Read the whole thread jackass.

I bought the car with this setup, previous owner used ls1edit to tune it himself. I did not want to hear it would be in the tune because they cost far more than just a CPS sensor or something like that.
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Old Feb 12, 2009 | 03:14 PM
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[QUOTE=stoverz28;11039462]^^Read the whole thread jackass.

Nice Response, this even goes with purchasing a performance vehicle, read your own statement.

[QUOTE=stoverz28;11028076]Thanks for the replies, although its not really what I wanted to hear just because of the cost associated with a good tune.

Sounds to me that you do not want to pay for a tune. Anyway hope someone helps you out, even with your childish answer....
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Old Feb 12, 2009 | 04:40 PM
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Dude just GTFO. Your not being helpful, just telling me things I ALREADY know. It's common knowledge that cammed cars will need a tune, nothing new. And I don't want to pay for a tune, but if I need to (which it sounds like I do) then I will.
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Old Feb 13, 2009 | 06:41 AM
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Then just go to A.R.T. their in Buda for a Tune, Hope now that helps you...
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Old Feb 13, 2009 | 11:35 AM
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I didn't think they touched f-body's anymore. Thought they were mostly vipers, I'll go by there and see.
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