Hey, I'm driving a 95 E 150 5.8 propane conversion yesterday and it died.
I hadn't been having any trouble with ignition previous. Cranks no start. There
is spark at end of coil lead wire ,fuel is present.No parts have ever been
replaced in the ignition system. I know it could be several possibilities or
combinations of. Switch, I m, pip, cap, rotor. My question is this Where is the
best place to start and probable cause.Simple tests and ellimanations .Thanks

 

Check spark further downstream of the coil wire. If you have spark to the plugs it has to be the fuel system. Failure of the PIP or ICM would cause loss of spark, at least intermittently.

If you are sure you have fuel its probably the rotor/cap.

 

Thanks for the suggestions.Change the cap and rotor, then rechecked the fuel
supply and the poblem ended up being a faulty shut off to motor.Runs better
than ever now