Ford Repair: 86 f150 will not start, chassis wiring, degree in electrical engineering

Question
Hi Steve,

My father gave my son a 1986 Ford f150 SHORT BED WITH THE 302 EFI. {Opps sorry 'bout the caps} This beast has had the same intermittent trouble for 20 years. Some times it starts, other times it will not.

We have replaced all the fuel pumps,[duel tanks], and related pieces. Went through all the smog stuff, [old Calif rig]...and replaced the "brain" with one from a wrecker. It will start once but not twice. It has died in the fast lane more than a few times also.

OK, now having said that, The guy at the shop says he can't find a new module for that rig. None made for 1986. I understand it's the first year for the injection system, and this might be a 351 with the EFI stuff on it. Was there some kind of weird child in that change over year? I have documentation from new here so I know the motor hasn't been swapped out.

Any suggestions as to why this has been a lemon all these years and what I might try next will be much appreciated.

Thanks!

Brian

Answer
Brian-

  It sounds to me like there's a loose wire or connection somewhere.  Where?  I have no idea.  If I had to hazard a guess (and I do), I'd guess it's either in the chassis wiring harness (and believe me, that's not something you even want to think about messing with yourself unless you have a degree in electrical engineering) or somewhere in the ignition/starter area.  Since it has happened while the truck is running, I'm much more inclined to disregard the starter, but I suppose it's possible.  Hope this helps.

Steve