I have a 1990 Formula Firebird 305 TPI, and I have been trying to get it running right for a while and keep having the same problem. Most of the time it will start and run for a while just fine when going on one trip to one place and back. But then sometimes after it warms up for a while, or I run local errands where I have to turn the car on and off frequently, it starts to act up. It will hessitate really bad and sometimes stall, and then it won't run right for a couple hours and up to a couple days. I did all normal tuneup work, even replaced fuel pump and filter and relay, replaced from cat back including O2 censor. Any info or ideas would really help. Thanks.

 

Consisting of what though? I had a similar issue awhile back, and it turned out to be the ignition module believe it or not, it was starting to go. What exactly, aside from the things mentioned, did you tuneup....?

 

I am going to second the ignition module and recommend you look at the pick up coil in the distributor as well. Both of these plagued me for weeks before I figured it out. The first time it was the module and the second time it was the pick up coil. I was having similar problems both times.