Hi guys. I have a 96 LT1 with auto trans in my truck. The only aftermarket parts on it are Cold Air Intake and headers. I didnt do the swap so I dont know whats wrong with the engine. If I start it cold it runs fine for aprox 3-5 mins. Then begins to stumble.(poor acceleration,rough idle,and backfire) If I turn it off and restart it. It stumbles at first goes away then comes back. If I unplug the air temp sensor on the intake its the same problem just takes longer to happen. I took it to auto zone and it threw 22 codes all MAF O2's right and left bank lean same thing just more than once. I dont know much about Electronic Injected engines just the basics. Does it need to be tuned for the headers and intake. I want to be sure its a computer problem before I spend an arm and a leg to have this thing put on a dyno. If anyone can offer any advice or has had this problem I would greatly appreciate the help.

 

Doesn't sound like a computer problem, as much as an electrical problem. MAF plus O2 codes make me think it might be a fuse. Check your wiring.

Don't put it on a dyno until it's running right. You're wasting your time and money if you do - contrary to what a lot of people believe, "programming won't fix broken cars". Cold air and headers won't make that much of a difference in how it idles and runs around town.

 

The person who owned it before me rewired the fans to a seperate relay and theres some wires that are clipped off at the fuse and relay box. Also my electric air pump doesnt kick on. I had a fuse that wasnt blown but melted. I know one of the wires has to do with the fuel pump because when its not grounded the fuel pump wont kick on. Could this cause the problem Im having. Im not to familar with the wiring on these engines. Where can I get a wiring diagram. Thanks for the help!

 

Might start here with wiring:

http://www.shbox.com/1/4th_gen_tech1.html

But it sounds like you have a mess on your hands. I hate hack job wiring.

 

Amen. If this guy did not know what he was doing, you have real problems. He probably didn't unless he has done multiple conversions already in the past unless he is an idiot...but you are confirming that he is. I did not do the original conversion on my RX7 and the guy just wired stuff together and very much incorrectly. I am currently in the process of a complete rewire of the car and engine. It is a bitch.

You have both a wiring issue and a computer issue and one can cause the other. Freebie note: all power must come the battery. If from alternator, you must rewire but it may have already damaged the PCM. This is what happened with mine.

My suggestion: Get tuning software and learn to tune. Sadly, the 96 PCM are the hardest to deal with. If it was 94-95 or 98+, you would have an easier time. You have 22 codes and this chump that you bought it from knew nothing and just started pulling things and did not program them out of the PCM.

Honestly, if you bought a truck like this, you should be expected to learn this. No one can really do a conversion correctly without doing it himself. The person that it is sold to must know every nuance of that conversion and that just takes time.

I can make some suggestions on issues to check but you have 22 codes! You have a lot to deal with. Most can be programmed out but some will be head scratchers and that is what takes your time.

Get the actual GM service manual for the 96 (F-body or Y-body whatever it came out of). This is IMPERATIVE. when you do a conversion, you must understand every wire and correct location. A BONUS and free ebay search for you: http://cgi.ebay.com/ebaymotors/1996-Chevy-Camaro-Pontiac-FireBird-Service-Manuals-2_W0QQcmdZViewItemQQhashZitem3a52b10ffbQQitemZ2504 95438843QQptZMotorsQ5fManualsQ5fLiterature assuming it is a F-body PCM. Also, I suggest the complete manual of your truck. Not that damn Chiltons crap but the actual manual from the manufacturer.

Good luck. I have had my car for 2 years and have worked on issues from day 1 with that damn thing because of what the prior owner did and did not do. It has taken me 2 year and I have another 2 years to go before it is in pristine shape.

I could probably take your truck and solve your issues in a day because of what I know now and probably would buy it off of you just to do that (for the right price) because honestly it will take you probably 30+ hours of your time to get this right. I have spent probably 200+ hours on my car getting it right.

It is reality!