1990 F150 4x4 - 302

Needing some ideas as to what's wrong with my truck. Truck was running fine and then suddenly it died on me one day. Truck will restart but runs poorly. Runs really rough, keeps stalling, fairly black exhaust, appears to be flooding. After a few days of working on it with no results, it suddenly ran normal again for about ten minutes, then back to the same issues. I've replaced the fuel pump relay and the fuel pressure regulator. Fuel pressure is normal, vacuum is normal. Also checked/cleaned the grounds that I could find. The fuel pump relay is clicking on and off at random times, and when the fuel pump primes, it sometimes primes for the normal second or two and then other times it stays on. I hotwired the fuel pump on to bypass the fuel pump relay but the truck still runs poorly. I'm kinda thinking maybe the computer is the issue but not sure. Any thoughts or ideas? Thanks

 

Try looking at the MAP sensor. Your symptoms describe exactly what happened when my MAP sensor went out.

 

Ok, I'll try and test that sensor tomorrow. Thanks

 

Tested the map sensor. It checked out good. Any other ideas/suggestions?

 

Check for codes.

 

Ya I tried to get codes before. Tried the jumper technique but it didn't work. The engine light did come on when the problem first started though and is still on. Tried a code reader today with the same result. It could not communicate with the computer.

 

That usually means bad computer.

 

Finally got a computer and changed it out today. Problem solved, it was a bad computer.

 

Thanks for the update.