I have a 97 F150 with the 4.6L. I was driving down the interstate when it slowly started to lose power. By the time I had made it 4 miles, I could barely go 30 mph. The vehicle will barely run on maybe 4 of the cylinders. Short list of what I have repaired/checked with no luck.

Cam positioning sensor
crank shaft positioning sensor
fuel pump
fuel filters
mass airflow sensor
fuel pressure regulator
valve timing
verified no stuck valves
plugs/wires/coils
computer
egr valv
battery

I have pulled different plug wires off and determined this is not isolated at one side of the motor. At this point, I am inclined to believe it is an ignition timing problem. It did backfire on me when I was using ether to get it started.

I am out of ideas on this one. Would appreciated any help.

thanx,

 

what plugs and wires did you use?

 

Any codes? Wires hooked up in the correct spots? fuel pressure is good? not smoking is it(head gasket)? water in fuel? just some ideas that come to mind.

 

I don't remember off the top of my head the brand name of the plugs and wires. It was the more expensive brands that Autozone carries.

There is nothing to inidicate head gasket, never smelled coolant, no water in oil. Also, doesn't appear to be isolated to one side of the motor.

Fuel pressure is fine.

 

also, no codes, no smoke

 

well wires from autozone explains alot right there. half the wires there are no good while sitting on the shelves. and the modular engines only like motorcraft plugs so that could be your whole problem.

 

You could also have a clogged catalytic converter.

 

Thats a good possibilty, had not thought of that