I just bought this '89 IROC with a 305 TPI, standard tranny. It stalled and wouldn't crank on the second day I had it. We replaced the distributor thinking that would fix the problem. By this time, it was cooled down and so I ran it around town for about 30 minutes and it stalls again and wouldnt crank back up. So, on another day, we replace the computer in it because there was no fire to the injectors. The computer helped a little since it cranks just fine but stalls again when it gets warmed up to about 170 degrees. We tried to replace the MAF thinking that would fix it, but it didn't help at all. The injectors are receiving a signal, but a weak or unsteady signal. What could the problem be?