My 87 4x4 302 FI, 4sp w/ac will run for appox 30 minutes then die. Mechanic has checked both tanks and electric pump. All appear to be new and operating properly. Trouble is the wiring harness has been messed with, some wires spliced, etc. I believe I need to just replace the whole engine compartment harness. Does anyone know where I might locate one?
Thanks

 

Did you check the ignition coil? Those tend to quit working when hot when they go bad.