ok so i ahve had alot of problem with my aveng baught the car for 1800 and in the last 6 months put 1400 into it!!!i have changed the fuel pump crank shaft censer plugs and wires brakes roters. my machanic thought my pcm was bad because it would start run then die out of noware in about five min. then it wouldent start for anther two or three hours. so he sent it to some place in phily to get recalibrated and when we got it back and it wouldent start. so we sent it back. last week i got it back for the second time we put it in it started right up. i was so glad......then it died and wont start back up.then i found a 96 avenger with the same engine a 420a. baught the pcm off him for 100 and he says it only uses one computer is this true??our uses two right. the pcm and the ecu??any ways whats goin on here?? o any would a v6 pcm work for a 4 cylender??

 

Try changing the ASD relay and fuel relay. A I4 manual car will only have an ECU, so this is true. An I4 auto will have an ECU and PCM (just like an auto V6). One more thing, you can't use an I4 ECU with a V6 motor or vice versa. The timing and fuel maps are completely different.