i have a 1990 f150 4x4 with the inline 6 motor. In the morning when I try to start it, it stumbles and stalls. I then step on the gas peddal(fuel injection should not need to do so) then it will turn over. If I go to drive it in the middle of the day after sitting in the sun, it will just fire right up, even if it sat for a couple days. this morning it took about 3 to 4 time of trying to start it, and once I was up an running about 3 miles down the highway, it just shut off dead. It would not start up right away, then after a couple minutes started only to go about 100 yards. made it to my mechanic you said fuel pressure is normal, and has no clue what the problem could be. Only saying seems electrical. I would appreciate any help you all might have. As you all know a 1990 long bed sitting on 32" tires is pretty kick ***, so I want to get to driving it. Thanks all.

Volkoff

 

Check your battery's voltage. Alternator could be going south.

 

Check for vacume leaks.

 

Sounds like your alternator is bad, I've had that kind of thing happen to me (not a Ford) a while ago. Are you headlights or panel lights like really dimmed when the engine is running?