Mechanics

F150 PICKUP RUNS ROUGH OR LIGHTLY BUCKS WHEN DRIV

1995 Ford F-150

Engine Performance problem
1995 Ford F150 6 cyl Four Wheel Drive Manual 95000 miles

I am having a problem with my 95 F150, 4x4, manual tranny, straight 6 pickup. It is having a problem where it lightly " bucks" when driving at a steady speed. When idling or accellerating everything seems fine and runs smooth, but has the rough type of cutting out while at a steady speed and load (40 - 45 in 4th, but also in other gears too).

I changed the fuel filter, performed tune up (plugs, wires, rotor, and cap, air filter) with OEM parts. Thought maybe fuel pump, but it occurs regardless of which tank I use. The thorttle body was also cleaned and I have used injector cleaner in my engine a couple of times. A friend took a ride with me and said he didn't think it was fuel. Could it be something with the tranny? Computer? Could this be tied to the EGR?

Any assistance would be appreciated.
Avatar
Earwig
February 10, 2009.



If the RPM's are around 1500 to 1800 it is the fuel pump. I have a 91 and it does the same thing. My front tank pump finally died so right now I am running on the rear only.

Tiny
TexasTurkey
Feb 13, 2009.
I was originally thinking it might be that, but it happens the same using either tank and istn't the fule pump in the gas tank? If so, it would be too odd that both go out at the same time, isn't it?

A modification to my original post.

I notice that it doesn't happen when it is cold, but when my temperature gauge gets to the line at the bottom of the " normal" range is when it begins.

I wish I had a tach so I could nail it down to certain RPM's, which would be helpful.

Tiny
Earwig
Feb 17, 2009.
Ford had a recall about the fuel pumps and the transfer switch. Here is one of the many links about the fuel switch. They used a similar system until about 2000 so it should pertain to your truck also.

Tiny
TexasTurkey
Feb 17, 2009.