Hello,
I got this 1989 mustang 5.0L 5 speed car, with a harness outta I dont know the guy had told me it was out of another 1989 5 speed car. the engine was out on a stand and the engine harness and ecu was sitting in the back. got the car for a real steal deal.
Anyways the guy had told me this connector (ford motorsport part, cant remember the part number on it) which was placed between the A9L and the engine harness was some sort of performance chip and to leave it in the harness so I did. Once I got the car all together I went to check if I had a working fuel pump, turned the key with no response from the pump. and slowly started to get the smell of electrical burning, after going threw the "101 fuel pump no run diagnostics" and tracked it down to the only problem could be the the A9L. so I unplugged the thing from the harness and noticed a burn mark cant remember the pin number between the A9L and the "performance chip" (Im guessing around pin 36 or pin 26). I then unplugged the "performance chip" and installed the A9l straight to the harness and voila I had a very quiet but running fuel pump... I cleaned up and thats as far as I got that week.
The following weekend was finally time to start my 5.0L v8 up and hear it run for the first time, Over the week I looked up that "performance chip" and a mustang guru had told me its for to convert and older speed density computer to run MAF or run a MAF harness this is why Im asking for the speed density computer pinout diagram.
Anyways I went to start the car, she now would not crank from turning the key. was confused about that as the solenoid was new so I went and turned the car to run and got out and crossed the solenoid. she cranked but no fire? slightly confused I checked for spark which it had and checked and double checked the timing which was good and tried again... no fire... so I poured sum gas down the intake and I got a nice little pop coming from the pipes so I figured...must be a lack of fuel. checked the injectors which were not firing. so I checked fuel pressure which was barely there then I went to go check the pump again. Now it will only run on start and not on run. wont keep the prime at all. like the pump will run under cranking but not while in run mode. after long and hard diagnosing the issue it came to one thing again.... the A9L or the ground on the A9L. so I pulled it off and took it apart and sure enough pin 1 (i believe) had shorted out against the case and fried the connection.
Now Ive picked up another 1989 mustang 5.0L stick A9L from a pick-n-pull, the only one even remotely near my location and Im wondering what EXACTLY fried the old one. Was it the "performance chip" or was it something else. Ive checked my HEGO harness and it is correct for an A9L and Im going to double check all my wiring again but Im pretty sure its all correct. Im confused because the fuel pump ran for sure without the "performance chip" installed at least a few times in "RUN" mode, but not the following week when I went back to start it. I just dont wanna fry another one, dont know if I can find another one!
please gimmie a hand anyone, kinda desperate to get this thing going now and I just dont know exactly what couldve fried. I figure a 86-87 pinout might give me at least somewhere to be able to compare what exactly went wrong with that "performance chip" installation.
thanks
-David
I got this 1989 mustang 5.0L 5 speed car, with a harness outta I dont know the guy had told me it was out of another 1989 5 speed car. the engine was out on a stand and the engine harness and ecu was sitting in the back. got the car for a real steal deal.
Anyways the guy had told me this connector (ford motorsport part, cant remember the part number on it) which was placed between the A9L and the engine harness was some sort of performance chip and to leave it in the harness so I did. Once I got the car all together I went to check if I had a working fuel pump, turned the key with no response from the pump. and slowly started to get the smell of electrical burning, after going threw the "101 fuel pump no run diagnostics" and tracked it down to the only problem could be the the A9L. so I unplugged the thing from the harness and noticed a burn mark cant remember the pin number between the A9L and the "performance chip" (Im guessing around pin 36 or pin 26). I then unplugged the "performance chip" and installed the A9l straight to the harness and voila I had a very quiet but running fuel pump... I cleaned up and thats as far as I got that week.
The following weekend was finally time to start my 5.0L v8 up and hear it run for the first time, Over the week I looked up that "performance chip" and a mustang guru had told me its for to convert and older speed density computer to run MAF or run a MAF harness this is why Im asking for the speed density computer pinout diagram.
Anyways I went to start the car, she now would not crank from turning the key. was confused about that as the solenoid was new so I went and turned the car to run and got out and crossed the solenoid. she cranked but no fire? slightly confused I checked for spark which it had and checked and double checked the timing which was good and tried again... no fire... so I poured sum gas down the intake and I got a nice little pop coming from the pipes so I figured...must be a lack of fuel. checked the injectors which were not firing. so I checked fuel pressure which was barely there then I went to go check the pump again. Now it will only run on start and not on run. wont keep the prime at all. like the pump will run under cranking but not while in run mode. after long and hard diagnosing the issue it came to one thing again.... the A9L or the ground on the A9L. so I pulled it off and took it apart and sure enough pin 1 (i believe) had shorted out against the case and fried the connection.
Now Ive picked up another 1989 mustang 5.0L stick A9L from a pick-n-pull, the only one even remotely near my location and Im wondering what EXACTLY fried the old one. Was it the "performance chip" or was it something else. Ive checked my HEGO harness and it is correct for an A9L and Im going to double check all my wiring again but Im pretty sure its all correct. Im confused because the fuel pump ran for sure without the "performance chip" installed at least a few times in "RUN" mode, but not the following week when I went back to start it. I just dont wanna fry another one, dont know if I can find another one!
please gimmie a hand anyone, kinda desperate to get this thing going now and I just dont know exactly what couldve fried. I figure a 86-87 pinout might give me at least somewhere to be able to compare what exactly went wrong with that "performance chip" installation.
thanks
-David
