i have a 91 ford f150 with a 4.9 straight 6, and an automatic transmission. around town the truck runs pretty much fine, However going up hills, the engine skips.. its not full out sputtering, as if it were running off 3 cylinders, but every second or two it will skip.. like a misfire, Generally the less gas i give it the worse it is.. I can put it to the floor, and it will accelerate up the hill, and might skip once or twice while my foots on it, But nowheres as bad as when im putting along at 30-35mph.
It also does this in high gear on the highway.. If i am trying to stay along at 65mph, it skips pretty badly. It has started getting worse over the past week or so..
I have changed the plugs, and wires, however i did not do the cap, rotor or pcv valve. The air filter is new, And i am not sure when the last time the fuel filter was done. I just recently bought the truck, the guy i bought it from said it had a recent tune up. And when i pulled the plugs, They were in good shape. actually they looked pretty new. But the wires were original to the truck. So the fuel filter and pcv may or may not have been done when the plugs were changed last
I know i should start by doing the cap and rotor, My question tho, is what else could this be? I had a ford crown victoria with a 5.0, and an atomatic, that did the same thing.. Even after doing the cap, rotors, plugs, wires, and fuel filter. they helped, But the car still skipped on the highway.. i dont want to keep throwing money at the truck without addressing the issue. Any ideas? The truck has around 150,000 miles on it. It gets me around fine, But its annoying, And i dont like taking it on the highway just because of the skipping. Any ideas on what else to look for?
It also does this in high gear on the highway.. If i am trying to stay along at 65mph, it skips pretty badly. It has started getting worse over the past week or so..
I have changed the plugs, and wires, however i did not do the cap, rotor or pcv valve. The air filter is new, And i am not sure when the last time the fuel filter was done. I just recently bought the truck, the guy i bought it from said it had a recent tune up. And when i pulled the plugs, They were in good shape. actually they looked pretty new. But the wires were original to the truck. So the fuel filter and pcv may or may not have been done when the plugs were changed last
I know i should start by doing the cap and rotor, My question tho, is what else could this be? I had a ford crown victoria with a 5.0, and an atomatic, that did the same thing.. Even after doing the cap, rotors, plugs, wires, and fuel filter. they helped, But the car still skipped on the highway.. i dont want to keep throwing money at the truck without addressing the issue. Any ideas? The truck has around 150,000 miles on it. It gets me around fine, But its annoying, And i dont like taking it on the highway just because of the skipping. Any ideas on what else to look for?