Differences between 1996 and pre-OBDII engine electricals
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Differences between 1996 and pre-OBDII engine electricals
Hi everyone!
I just acquired a 1996 F150 4x4 truck with a 5.0 engine and E4OD trans as a spare time project. I bought the truck as a non-runner from a dubious fellow and basically all the info I was given on it was that the engine was replaced with a 5.0 engine from like a 1989 Mustang.
The guy I bought it from said the wiring harness from the Mustang was installed but with the PCM from the truck. I have no clue if any of that is true since he didn't quite seem very knowledgeable.
I was able to get the truck started and it actually runs much better than I thought it would. Transmission shifts smoothly through all the gears, surprisingly. The only issues I came upon so far is that the engine won't crank when turning the key, but does start when jumping the starter relay on the fender, probably has bad wiring from the ignition switch to the starter relay I'm guessing. Also, the airbag light flashes occasionally while the truck runs.
Anyways, long story short, I'd like to figure out which engine harness is installed on this truck. I know that 1996 was the first year of OBDII and was wondering what was unique to the engine electricals for the OBDII 5.0 F150 or how I can identify if the engine has OBDII electricals or OBDI. Any replies would be much appreciated, thanks for reading!
I just acquired a 1996 F150 4x4 truck with a 5.0 engine and E4OD trans as a spare time project. I bought the truck as a non-runner from a dubious fellow and basically all the info I was given on it was that the engine was replaced with a 5.0 engine from like a 1989 Mustang.
The guy I bought it from said the wiring harness from the Mustang was installed but with the PCM from the truck. I have no clue if any of that is true since he didn't quite seem very knowledgeable.
I was able to get the truck started and it actually runs much better than I thought it would. Transmission shifts smoothly through all the gears, surprisingly. The only issues I came upon so far is that the engine won't crank when turning the key, but does start when jumping the starter relay on the fender, probably has bad wiring from the ignition switch to the starter relay I'm guessing. Also, the airbag light flashes occasionally while the truck runs.
Anyways, long story short, I'd like to figure out which engine harness is installed on this truck. I know that 1996 was the first year of OBDII and was wondering what was unique to the engine electricals for the OBDII 5.0 F150 or how I can identify if the engine has OBDII electricals or OBDI. Any replies would be much appreciated, thanks for reading!
Last edited by OBSFordTruckEnjoyer; Dec 14, 2025 at 06:58 AM.