Help! New to Fords; here is my sad story: I've had a really good "working" truck, one that I use to go to the dump, haul woodchips, etc., that I purchased from Or DOT thru E-bay. The truck's been running very nicely for over two years, until recently -- on the way back from a dump run, with no load, the poor thing started missing/sputtering and lossed power while climbing up a long but shallow hill. First thing I did way scan the instruments -- check engine light illuminated,and the coolant temp was erratic, pegged, and finally died. Thought I possessed excellent troubleshooting skills, but to no avail. First was the replacement of the ect sensor, and an ignition component replacement (plugs, wires, cap & rotor, etc...). Idles o.k. for a cold blodded 'witch', but still bad power. Pinning out the elex harness and computer didn't help, either. Thought that I was too focused on ignition and EEC-IV "stuff", so replaced the fuel filter. Still no joy..... Pinned the TPS, resistance between 'TPS' and 'Sig Rtn' went up when the throttle was turned towards more power -- thought it should've gone down.......but I'm making a test point pigtail and will re-ck it with the engine on. More info: F250 w/3sp automajic, what I think is a 351C, but it might actually be a 5.0 (302? -- and if so, how do I find out?) ANY help will be appreciated.....

 

Your engine is a 351 Windsor if it is stock. If it is a 302, it should say "FORD 5.0 LITER EFI" on the intake cover. If it is a 351 it will say "FORD 5.8 LITER EFI". If it is carbureted it will say "5.8 Liter 4V H.O." on the air cleaner. The 351 got EFI in '88, so I believe yours is EFI. Some of the earlier EFI engines will say "FORD ELECTRONIC FUEL INJECTION" only.

But in reponse to your problem, I would have to say check to make sure your wires go to the correct cylinder, also check to make sure your O2 sensor is good. Also check your fuel pressure regulator, sometimes that will cause the motor to run like crap if it is bad. I believe your engine fuel pressure should run about 35-40 psi when the regulator is good.

If I had to guess, I'd say its the fuel pressure regulator.