Ok i have a 96 Trans am its 355.. ported heads ,forged bottem end, ported intake, throttle body pretty much everything bigger injectors, fuel pump msd coil.... i just put on a brand new GM opti spark taylor wires and NGK plugs thinking it would fix my problem the car runs and idles fine but just doesnt have the ***** it had before i go to punch it in second gear and it goes nowhere compared to before it would go all over the damn road.. i changed the opti and pigtail and plugs and wires thinking that was the problem..the car has been sitting for awhile so i dont know if its bad gass i took it around today for awhile on the highway with some good gas and still runs like it has no ***** i mean its a fully built 355 and it wont even spin them in second no more.. if you guys could maybe help me figure this out.. the car use to be a beast..also i forgot my connector on my maf or the pigtail one of the wires had ripped off so i thought that was it also and i purchased a new one and just spliced the wires in and put the new connector on made it idle better but still runs like dog ****..

 

Did you get the car tuned?

 

Yes i got it tuned by pcm for less i mean it was a mail order tune.. but when i first got it on it ran like a raped ape then it just started running like **** i had a summit racing opti and a bad opti pigtail so i thought it was that or my opti going out since the gm opti for these cars is like the best you can get.. so i bought a GM opti new pigtail brand new taylor wires and new plugs and it still runs like ****..

 

Also just a question my tune is set for everything for my car but i tuned it for a 58mm throttle body and i have a 52mm on right now would that effect the way its performing.. i planned on buying a 58mm thats why i did that.. but im not sure if thats whats making it run this way..

 

yea that could be making it run lean at the top end i suppose

 

another thing lol sorry guys could it be my exhaust leak all my exhaust is c clamped at the headers to the y pipe and its leaking very bad before the 02's you think thats another reason why its running the way it is not getting right 02 readings..

 

Fix your known issues first.

 

If you have that bad of a leak before the 02's then you could be causing a false lean condition which inturn your PCM will dump fuel and make it extremely rich, are you smelling rich/fuel exhaust? Anyway to hook up the PCM and datalog it so we can see what is going on? Lastly, take your ICM, MAF and coil to AZ or Advanced to have them test it as it could be one of these even though the COIL and MAF are new.

 

ok i just got it scanned and it says three things hopefully one of theses is the cause of so much power loss.

1.MAF sensor came up with something wrong with it.

2.it says skip shift 1 to 4 upshift solenoid system control fault.

3.TP throttle position sensor.. says the pcm has determined that the input from the throttle position sensor is higher than expected for the current engine operating condtions. so do i need to replace it???

i know where my maf is and ill check that but where is the throttle sensor and the skip shif solenoid at? .. and will all these effect my performance the way it is right now..

 

MAF and TPS issues would definitly cause issues. Is the MAF new? If not replace it and as to the TPS, have you ever opened up your TB by the adjust screw as that could cause the TPS to be off. If not then replace your TPS, pretty cheap. And rescan!!

 

Post the exact Pxxxx codes. That will make it easier to help you. There are at least 4 different MAF codes for the LT1 (OBD-II).

The skip shift solenoid is on the drivers side of the T56 tranny. Do you have the skip shift solenoid unplugged to defeat the 1->2 shift from being blocked? If you disconnect the harness connector you get a code. OBD-I the code does not turn on the SES light, in OBD-II it does. You can elminate the code with a 2Kohm resistor pushed into the harness connector.

For the TPS, there are 3 different codes. P0123 sets when the TPS voltage exceeds 4.9V for more than 1 second. It may be the TPS sensor, it may be the wiring. A simply measurement with a volt meter will tell you which it is. Probe between the blue signal wire and the black ground wire in the harness connector. With the key on, throttle closed, should read less than 0.90V (0.67V seems to be a typical stock reading). As you slowly rotate the blades open, the voltage should increase slowly, to a peak of less than 4.9V at WOT. If you get results that are different than that, pull the harness connector off, and measure between the blue wire pin and the black wire pin, and it should be very close to, are actually = to 0V. If its not, its a harness problem. If it is, its a sensro problem.

Generally a good idea to make a simple measurement, rather than just replacing parts at random.

 

the codes are p0123, p0100, and p1657
also when i hooked my new pigtail up to the maf i had a pink wire a black wire and a red wire.. but on the harness to the maf theres a yellow wire a pink wire and a black wire.. i hooked the black to black and the pink to pink and the yellow to the red... i dont know if thats right or not..

 

They are torx bits. I believe the are #4's