Sputtering and backfiring after big install
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Joined: Feb 2005
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From: Valdosta Ga.
Sputtering and backfiring after big install My 93 Trans Am will sputter and backfire like crazy at low RPM's but if you give it gas it will run alot better. I just installed everything in my sig along with the MSD 8.5 wires and NGK TR 55's. The coil is still stock so I might try that. The thing that gets me is the plugs and wires were badly worn when I replaced it all but the car ran perfect! Now I put all these nice parts on and it runs like total crap. I disconnected both O2's tonight and drove it about 1 mile and barely made it home. I was sure that was it but I guess not. I still have open Y-pipe right now but I ran it with open headers, untuned for a few days just sitting in the garage. I wonder if that fouled the new plugs? Any suggestions? Im going to recheck the wires and look at a couple plugs soon.
Also, do these MSD super conductor wires click when they are all the way on the plug becuse I pushed hard and never heard a click out of any one of them like most plug wires do.
Also, do these MSD super conductor wires click when they are all the way on the plug becuse I pushed hard and never heard a click out of any one of them like most plug wires do.
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Joined: Feb 2005
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From: Valdosta Ga.
It was installed right. Timing dots were lined up and the opti went on flush before I put the bolts in so it should be on right. The car fired up immediately the first time and it has idled well since the first start. Just sputters when its put in gear at low RPM. Sometimes its really bad and other times not as bad.
Joined: Jul 2007
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From: Ringoes/Flemington, New Jersey
make sure your wires are set up right, just double check everything. if it ran fine before, there is no reason why it should act up now. unless u effed something up 
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From: Valdosta Ga.
Its an auto and has a mail order tune from madtuner.com. I just went out and pulled a couple plugs and thay are pitch black. Covered with soot. Thats probably from running it before the tune. These are new plugs also. Think thats whats causing it? Im going to clean them all and see if it helps.
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fouled plugs can definately cause some running issues lol
I'm sure a stock stall isn't helping your low rpm driveability but that's a pretty mild cam so change the plugs and let us know what happens
I'm sure a stock stall isn't helping your low rpm driveability but that's a pretty mild cam so change the plugs and let us know what happens
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Joined: Feb 2005
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From: Valdosta Ga.
Well I cleaned all the plugs at 2.00 A.M. last night (love these Mac mids for that) and it runs pretty good now. All of them were very black. It runs good but it doesnt seem like it has the power it should. I just installed everything in my sig and it only feels slightly faster than before. Mostly feels sluggish down lown until about 2,500 RPM's. Do you think this is because I was driving with the Y-pipe open? Im going to get the rest of the exhaust on Mon. and see what that does. Any thoughts?
after dumping about 5 grand into this stock shortblock I realized I should have stuck to bolt ons. At least with bolt ons there is a point where you can sit back and say that you can do no more. As soon as you pull those heads off the sky is the limit. Your savings account and your marriage are all in jeopardy for a few horses. I was thinking spark plug wires but it seems like you got it figured out 
regarding to your question about back pressure... you have long tubes? I installed longtubes on my car and ran it for about 3k miles like that.. ran like a rapped ape.. just killed 02 sensors a lot. I would say that NO the headers are not your problem.. although if you have shorties, im not sure.. it could be. Just saying what I have experienced
