Engine/Transmission (1998.5 - 2002) fuel pressure reading

[jtisdale]

These readings are from the outlet side of the filter, as the autometer sees it. I hooked up Briar Hoppers gauge at the inlet side of the filter. It showed the same at idle, but I lost . 5 psi at cruise, and 1-1. 5 psi WFO. Filter is new, and has less than 1000k on it.

Keyed..... 14

Idle... ... ... 12. 5-13

Cruise..... 10-11

WFO... ..... 7. 5-8



However, I do notice the gauge dips to 5-6 at cruise and might stay there for 5-8 sec. It also does it at idle, drops to 7-8. It doesnt happen very often, but it does happen.



NO FLUCTUATION in either gauges, as I had complained about before (when I was hooked at the vp44)

I guess I am happy for now...



If you dont know what your fuel pressure is, get a test gauge. Its cheap insurance. Dont delay, get one today!!

 

[Jack in Alaska]

Fuel pressure problems-finally

I have 92k mies on my truck with the original lift pump. I installed a Westach guage using an 18" grease hose.

The pressures have been (until yesterday) 14 psi @ idle, 11 psi crusing and 9-10 psi @ WOT and rock solid always.

Yesterday at start up(cold 55F) key on: 3 psi and then went to 0 psi. start up and idle: varies between 5 & 8 psi. Start to drive on highway: still varies but occasionally went to 12 psi.

After shut down and 1 hr stop it went to 14 psi, 11 psi crusing and 5 @ WOT.

Is the lift pump going south? Should I let it grenade the inj. pump and then get a new one under warranty? Should I go have the dealer give me his $. 02 worth?

The truck runs fine without any stumble or surging. My fuel mileage has degraded slightly in the last 6 months. From 19 to 17. 5 on the highway.

Any suggestions would be appreciated.

 

[WyoJim]

Jack... I would change the fuel filter first and it should only take about 15 seconds of the first starter bump to squirt fuel out the loosened 1/8 inch plug. If it takes more than one starter bump its probably the lift pump.



If it only takes the 15 seconds or less but still acts goofy as far as fuel pressure I would consider the sender.