Need help.
I have perfect compression, spark and fuel,
but truck is not running on 2nd and 4th cyl.
Its a 91 f250 with the 460 EFI.
I have replaced the lifters,(one was bad)
new plugs and wires, cap and rotor,
computer diagnostic shows nota.
Im about to lose my mind.

Check fuel injectors...

Sounds like an injector to me also, check with a multimeter and see if you have power going to the injectors while running if it will run. Otherwise sounds like time for new injectors.

Sounds like an injector to me also, check with a multimeter and see if you have power going to the injectors while running if it will run. Otherwise sounds like time for new injectors.


I thought about that too, and plan to get a whole new set, but
Ive switched injectors around and still have the problem in 2nd and 4th
cyl.

This is the original engine is it not?

ervinj

This is the original engine is it not?

ervinj
Yes it is.
Ijust cant seem to pin the problem down, I thought if it was the injectors, by switching them around the problem would move to another cyl.

are you getting spark on those cylinders?, try hooking up a noid light to those injectors. i believe you have a hall effect rotor in the distributor. sometimes they get cracked or magnetized which screws up everything. also check the wiring harness for those injectors, Ford wiring harnesses aren't the greatest.
good luck

also, could be a plugged EGR, they get plugged and only a couple of cylenders would get all the exhaust, but it would only happen at idle if your EGR valve was stuck open, which is very possible.

I have some advice you probably wont like it but here it goes.
Go put a chevy engine in it the only good fords have chevy engines in them. Plus it will be a lot more reliable.

i don't think so, if you are not here to help with the problem, go somewhere else. Check to see if the PCM is giving power to the injectors. BTW, i have had more problems with my chevy than any of the fords i own.