Welcome Visitor! Please take a few seconds and BillRod
Member
- Joined
- Dec 27, 2008
- Messages
- 219
- Reaction score
- 1
- Points
- 18
- Location
- Colorado Springs CO
- Make / Model
- Ford
- Engine Size
- 95=4.9L Others=4.0L
- Transmission
- Manual
Hi All
95 F150, Big six, 5spd, extended cab, dual gas tanks.
Few weeks ago I noticed an intermittent hesitation when driving using the rear tank.
Switched to the front tank all seemed ok so I figured it was the pump.
This week I noticed a similar hesitation using the front tank too.
I put my pressure gauge on the fuel rail and ran it out the back of the hood to watch it while driving.
Idle is 50psi, pressure raises to 60 psi under full throttle.
psi seems to be in relation to the amount of pedal I use, no pedal 50, 1/2 pedal ~54, full pedal ~58.
I guess that is how it should be?
Issue/Question: The needle jitters, it is never calm as one would think.
At idle it jitters maybe a pound or so. Half or full throttle the jitters varies a lot, either a little or as much as 8-10 psi. The only time the needle does not jitter is when I pull my foot of the gas and compression braking slows the truck.
Also I did feel the intermittent hesitations that started all this and that seemed to be when the need jitter was 8-10psi.
Should I pull the bed and replace the pumps? Is the extreme psi jittering enough to cause not enough fuel to let the engine run right?
History of the pumps: Bought the truck in 07 with original OEM pumps. Rear tank went out shortly after buying the truck, ignored it and used the front tank until that pump went out in December of 09. Replaced both original OEM pumps with AutoZone pumps in Dec 09. When I had the pressure gauge on the original OEM front pump it never jittered, it was nice and calm.
Any thoughts on any of this?
Thanks
Bill
95 F150, Big six, 5spd, extended cab, dual gas tanks.
Few weeks ago I noticed an intermittent hesitation when driving using the rear tank.
Switched to the front tank all seemed ok so I figured it was the pump.
This week I noticed a similar hesitation using the front tank too.
I put my pressure gauge on the fuel rail and ran it out the back of the hood to watch it while driving.
Idle is 50psi, pressure raises to 60 psi under full throttle.
psi seems to be in relation to the amount of pedal I use, no pedal 50, 1/2 pedal ~54, full pedal ~58.
I guess that is how it should be?
Issue/Question: The needle jitters, it is never calm as one would think.
At idle it jitters maybe a pound or so. Half or full throttle the jitters varies a lot, either a little or as much as 8-10 psi. The only time the needle does not jitter is when I pull my foot of the gas and compression braking slows the truck.
Also I did feel the intermittent hesitations that started all this and that seemed to be when the need jitter was 8-10psi.
Should I pull the bed and replace the pumps? Is the extreme psi jittering enough to cause not enough fuel to let the engine run right?
History of the pumps: Bought the truck in 07 with original OEM pumps. Rear tank went out shortly after buying the truck, ignored it and used the front tank until that pump went out in December of 09. Replaced both original OEM pumps with AutoZone pumps in Dec 09. When I had the pressure gauge on the original OEM front pump it never jittered, it was nice and calm.
Any thoughts on any of this?
Thanks
Bill
