My current car is a 1991 LX, original 5.0 automatic car. I bought it not running with a 5 speed and pedals already installed. I got it running then put my 306 in it and got that running till I discovered a broken piston, so now it has a 331. Ever since Ive owned it, there have been running issues, none of which were ever diagnosed or worked out since the vehicle had engine issues and never left my garage. The computer that was in the vehicle when I bought it was a Carquest reman and has none of the Ford part numbers or designations on it. When I called CQ to ask them what is was out of they were unable to tell me, and just said theyre catalogue stated Ford 5.0 V8. I wanted to skip the potential hassles of trying to diagnose issues if it had not quite the right computer, so I bought what I thought and was told was a good A9P from a local guy. So before I even test fired the car yesterday I installed my Moates Quarterhorse chip in the A9P and installed it into the vehicle to start with a known correct and good computer to tune it once the rings seated. Well..... when I went to start all I got was a cranks / no fire... Tested for spark, fuel press, timing and injector pulse and all were good. I noticed that the fuel pump was running all the time with the key in the on positon which usually indicates a bad computer.. Pulled the A9P out and put the reman CQ one in there and it started right up, fuel pump running for 3 sec then off like it should. The previous running issues are still present, and I plan to try and diagnose them before even starting to tune anything. I know a A9L computer will get fried when placed into a A9P harness because of wiring differences in the oxygen sensor harness, and an A9P can work in either vehicles from what Ive read. But what the hell can fry a A9P like mine is ?????? .. Im at a dilema as to what to do... these are the options I considered (#1) Put the Quarterhorse in the CQ reman computer and hope that I can make it work and that Im not wasting my time tuning garbage... (#2) By another computer (A9L or A9P) and hope that it is good when I buy it and theres not something with the car that can make the next one go bad.... All you gurus please chime in...