I also posted this in the TPI section but i havent gotten much help, I have a 89 GTA with a 350 TPI, i recently replaced the injectors and it ran great for a few days and then out of no where it started running like poop again. Im going to check the TPS Sensor but if it isnt that i have no idea where else to go, any suggestions. The car starts idles like crap, wont rev up and in general just runs like complete ****. Please any suggestions or ideas if you need to know anything more just ask. HELP!!!!!!!

 

Change vacuum lines. May be a problem, and if not, oh well you spend $5 to do something you should do periodically.

Also, whens the last time you have done a tune up?

Its an 84 (if it's the one on your profile) and the car is pretty old, parts need to be tuned up. Try there first before spending big money throwing parts at it.

 

It's hard to say exactly what might be going on. But, I would start by looking at the MAF sensor for the cause of not revving and idling like snot. With the key off, unplug the sensor and start the car. See if it runs better, especially if it revs and makes good power with the sensor unplugged. If so, you need to look for the problem with the MAF, MAF relay, or wiring. Another common cause of this kind of problem is a restricted catalytic converter. You can check for this by loosening the flange bolts on one exhaust manifold to allow exhaust to vent there and see if the motor runs and makes power this way. If so, you have a clogged cat.

I would be connecting my scan tool to this car to check MAF voltage and other PIDs for clues. A scan tool is almost indispensable in diagnosing these cars.