Engine/Transmission (1998.5 - 2002) Lift pump pressure

[CAW440]

I had the lift pump changed about 30,000 miles ago, starting this week my fuel pressure is now pegging my Westech 15psi gauge. It barely moves off the high mark at all. My question is this, do you think its the pump going out or a bad sending unit?

 

[SnoKing]

My guess it that you have a gauge problem. I thought about selling my test gauge after installing my Di Pricol in Cab, but decided to keep it just for times like this. SNOKING

 

[WTBurke]

It's good to have a mechanical gauge Tee'd off the same input to your electronic transducer type fuel pressure sensing unit. A glycerin filled 0-30 PSI type device is available from Grangers for less than $12 bux. This way you have a device directly at the input that is not electronic and you can trust it. (Providing you mount and feed it correctly)



There are 3 devices at Grangers cheep at $7 next is better (SGC) at $10 and the Ashcroft gauge at $12 being the premium. They are all available with 1/8" NPT males. These are very cool extreamly accurate gauges less than one and a half inches across the face.



Regardless of "electronic" or "mechanical" type telemetry devices... you want your typical range to be at 50% of maximum. So if 15 PSI is your window of operation the correct selection would be 0-30 PSI.



These glycerin type gauges are very common however, don't mount it near heat sources. The firewall is the best place for transition mounting.



I have Hewitt gauges which are mechanical in nature but, when I lift the hood... I still glance at my "glycerin-filled" gauge to confirm what I'm seeing in the cab.



Cost of this redundancy including gauge and brass 1/8" fittings from NAPA is less than $30 bux.



BTW this set up looks very cool and you never have to guess about what your seeing.



William

 

[PLaFrombois]

Where do you have it grounded in the cab? I had grounded mine on a screw under the dash until I was having the same problem. A washer on both sides of the ground connector and it's been working fine up until a couple days ago.

I just changed my LP, and the needle doesn't move off "0" until the trucks been driven for a while. After so many miles it works fine. I finally think I've figured out the problem. The guage doesn't like this 0 degree weather we're having. Once the cab warms up, then the guage starts to work. That's my conclusion until the temperature rises above 10 degrees.



Paul