I just bought a 91 F 150. for 600 bucks, because apparently it had a bad transmission, So I drove it and the truck shifted fine, Just a loud clunk when accel and decell, So I knew what was wrong with it, Got her Home changed the Ujoints, and now it shifts smooth, and great.

But heres the new problem that came up. It appears this truck has never been tuned up. I pulled the airfilter it was oily, and rusty. Old Old filter, changed rotor and cap. Wires look ok. But didnt have time to get to the plugs and other tune up stuff. So when Im driving, it Drives smooth but then it will start jerking lightly and shaking, espeically up hill its bad and espeically at low rpms in overdirve,, . And it looses alot of umphhff on the hill.

what would people recommend> I was thinking fuel filter might be clogged, and the plugs are bad?? I was also going to run some fuel injector cleaner through it. Anybody else have an idea,

Thanks alot CHEERS

 

Sounds like the old girl needs some TLC! What motor is it?

If its the I6, for some reason when i would let mine sit for a while, it would run like crap for about a day then it'd be good to go. That is, if it sat for like a month or two

 

302.. EFI. the motor starts right up everytime,. has 190k on it, doesnt smoke or anything cant barley even hear it run.. One tiny oil leak,.

 

complete the tune up and go from there. change the fuel filter for sure.

 

Almost 100% sure its plugs. Had the same thing on my old 99 Taurus a few years back when it was running on original plugs @ only 110k. Changed them out, ran a LOT smoother. No more shuddering.

 

Go ahead and replace the plugs and wires,sounds like it may have one or the other breaking down undera load.