Hello my name is mark i have a 92 f250 custom that has a problem. I have a 5.8 (351w) i jumped in it after work and on the drive home she was missfiring and not going over 20 m.p.h. i had her toed home next morning she wouldnt start. Spraid some starter fluid in her she fires up but she ether stalls out when driving or she missfires when you try to give her gas. When you turn the key the fuel pump stays on without shutting off like it should. Brand new fuel pump fuel filter and new alternator. Im starting to believe i have a bad pcm/eec. Any suggestions?

 

Yes when the fuel pump runs continuously before the engine is started that indicates a bad PCM.

 

Any idea where the pcm is located on this truck?

 

It's in the drivers side cab fender but is accessed from the engine bay by first disconnecting the wiring harness.. the rectangular shaped connector not the round one. Make sure you disconnect the battery first before anything else.