I just purchased a 1994 Ford F Super Duty. The truck is a 5 speed with a 460 EFI. Seems like the truck is low on power. It has a 4.63 rear end. When driving up hill's I lose 10 - 15 MPH, with downshifting into 4th gear. To me the truck should climb right up them with little speed loss. Here's what I have done so far:

New Plugs
New Wires
New Distributor Cap
New Rotor
New TFI module
New Fuel Filter
Lot's of injector cleaner

Any ideas where to go from here??

 

Tire size?
Codes present?
Ignition advance?
Fuel presure?

 

Could be a clogged cat.

 

The truck didnt have a cat on it when I purchased it. I aint throwing any codes. The fuel pressure is in the low 40's.

 

Are there any other symptoms? Does it run hot?

 

I can't find any other problems temp runs normal I'm at a lost.

 

maybe advance the timing a hair, or could be the motor is full of junk and needs a good cleaning... I would get a can of seafoam drive with it for est 50 miles and do a oil change on it, the slug could be holding you back some... Just some ideas but let us know if you figure it out!

 

Whats the mileage? Is it eating any oil/ blow-by maybe? Have you done a compression test on the cylinders?

 

if the cylinder test numbers are low after a compression test put a cap full of oil in the spark plug hole and see if that made the test number go higher.