I recently got my 1992 Tran am 305 running, the car was given to me me by my dad, who managed to blow out the forward cluthes in the tranny about 7 years ago. I rebuilt the transmission and replaced the fuel pump and fuel filter. I FINALLY(after 2 years of having the car) started it up. It started up just fine and idles perfect. It rev to 4500rpm just fine, no studder, or hesitation. but when i put it into gear to take in down the street itl do just fine until i hit about 20-25mph then itll just start cutting out and wanting to die unless i let of the gas then itll cruse just fine, i got it up to 35mph once, befor it did the same thing. if i stop the car and put it into park it wont rev up past 2500-3000rpm but if i turn the car of and start it right back up it revs up to 4500rpm just fine. Im at a total stop, the tps, fuel pump, fuel filter, are all new. the transmission its working great, the fluid isnt burned or anything and it shifts just fine, no slips.

I'm thinking the IAC might be bad, but i dont know how to tell. I was also thinking it might be the coil, or maybe the cap and rotor.

Any help would be greatly appreciated!

 

Anyone??

 

I have the same issue with my 90 Iroc. It starts and idles, fuel pressure is good at prime(key on but not started 46-47 psi), fuel pressure good at idle(36-37). Rev the engine in park, it dies at about 3000 RPMs. Will not go under load. Just checked my injectors' resistances, got 16.2, 16.3, 16.2, 2.3, 16.2, 16.1, 16.3, & 10.0 ohms, so I have 2 injectors going south. OEMs are ridiculously priced must now figure out best replacements. Sounds like your car has similar symptoms as mine, therefore, I recommend checking your injectors as well.
Regards

 

contact southbay injectors and replace those crappy multecs with Bosch III's

 

well that was another thought, before my dad hammered the transmission he had a half a tank of e85 in it, and it sat for about 4 years with that in the system, how do i check the resistance of my injectors? i hooked the car up to my computer and every thing check out fine, that i could with that. thanks for the help us019447!

 

what injectors should i get? i thought the 92 305 ran the 19lb injectors? but im not positive.

 

Unplug the connector from the injector(you''ll have to push the stainless steel clip inwards towards the injector to release the connector). Check resistance with a multimeter...mine is digital and set it to read ohms. Just place one probe on one tab of the injector and the other probe on the other tab of the injector. Per searching this site, the injector windings should have resistance of 16-17 ohms. Check each injector...if good, they should all be within 0.1-0.2 ohms of each other.
I'm considering the Southbay injectors. Others are mentioned, but I want to keep it stock flowrate. Per the forums, the 305 cu in stock TPI engine takes 19# injectors. Disclaimer: I'm not an expert. I'm going on researching this site and others.
Regards

 

us, you're right on so far. The people at Southbay know their stuff. They will get specifics on the car from you and get you the right injectors.

Poor ignition tune, especially tired wires can cause somewhat the same symptoms. The difference is that when wires are the problem, the engine will lose power at mid throttle and then generally come alive with more throttle pressure.

I have seen bad ignition coils or ignition modules cause this same type of symptom and the engine will behave just like it's not getting fuel. However, in this case, if you watch closely, you'll see black smoke from the exhaust, telling you that there is plenty of fuel. The ignition just isn't producing combustion. The test to verify this type of failure is to connect an inline spark tester to any plug wire and watch while you power brake the car. If ignition is your problem, the spark will drop out under load.

 

hmmm interesting, my car seems to be doing the same thing as crushers car! It'll idle fine but it wont accelrate or rev when it acts up. I notice that it usually hapopens when the car gets hot though.

 

Check the resistance on the injectors both hot and cold as injectors have
A tendency to shut down when they are hot which
Is indicative of coil failure

 

could it possible be my oxygen sensor?