I also have a 1987 f150 with a similar problem. I replaced every part of the ingition system looking for a solution, and finally discovered that a wire from the ignition switch to the fuel pump was loose. Thus, every now and then it would start, but sometimes it wouldn't start for days. I would check all the wire connections under the hood.
However ever since I replaced the wiper motor, switch, and intermittent switch on the vehicle the truck has been idling too low. At a red light the engine dies, and it is difficult to start again. Any thoughts? | 
Linear Mode
