I have a 1997 f150 with the 4.6l, the truck has 118, 000 miles on it. The problem I'm having is loss of power. I replaced plugs and wires, cleaned the intake, and changed the fuel filter. I had it put on the computer at the local dealership but nothing was found wrong. Need Help

 

Does it have loss of power at all RPM ranges?

Does the engine run smoothly?

Does the engine accelerate smoothly?

 

Did the loss of power just start happening, or is this something that has been going on for some time.

Does temperature have an affect on it ?

 

Have you replaced air filter? Also might try cleaning the Maf sensor and the IAT sensor.

 

The power loss problem has been going on over the last 6 or 7 months. The engine idles fine but when I put my foot in it for passing or taking on slopes this is when it seem not to have the power. Today I heard clatter coming from the engine during acceleration. I did change the air filter.

 

sounds like a lifter collapsing/stuck try changin the oil and maybe run some marvel mystery oil or somethin to clean it out