Engine/Transmission (1998.5 - 2002) Please help! Lift pump question.

[dknoch]

I just installed a westach fuel pressure guage and I am not sure if it is working correctly or if my lift pump is dying. When I first start the truck, I'll have 12 psi on the guage. If I drive away immediatly it will stay like that until I stop. When I stop, the guage will drop to about 4-5 psi and may or may not come back up to the 10-12. Also I bumped the starter to test the pump and I had a nice solid 15 psi and then the sound of the pump changed and the pressure dropped to about 5 psi. I re-bled the fuel line to the guage and and readings are still all over the place. I believe it is the lift pump but I would like a good arguement when I go to Dodge. Thanks for any and all help.

 

[jamnram]

my experience... (be warned bad speller)



hadn't test my presure in about 6k... put the guage on I bought from black mtn diesel... . results 2 lbs at idle... . 0 running...



called the dodge dealer, took it in and they said it was good... and my gauge was bad.....



called black mtn diesel... they said the gauge never fails... . most dealers have no clue... test it with air presure... .



called cummins to see if they had a pump in stock... explained the problem... service guy to me I'm fine don't waste your money... .



tested gauge with air presure... was perfect... thank you black mtn diesel...



rather an deal with the dealer under warrenty... bought pump from cummins in spite of the service guy...



installed and 13 lbs at idle... . 10 lbs at curise... .



hope the injector pump wasn't hurt... .

 

[fox]

When you bump the starter on these 24 valve motors the lift pump runs for about 30 seconds then shuts off. If you just turn the key on it will bump the lift pump to purge the lines, some of us see 2 lbs.



I'd think you should see the pressure drop as your right foot goes closer to the floor, mine does.

It never hurts to double check witha second gauge.

My guess is that you have a week pump.

 

[Paul Somers]

Jamnram

I have the Black mtn diesel gauge also and sometimes it reads zero. The gauge is ok but sometimes the shrodder(sp) valve doesn't open when installing line to filter. The protrussion on the supplied line doesn't stick out far enough to open the valve with out really tightening down hard to compress the rubber gasket.

 

[dknoch]

"Also I bumped the starter to test the pump and I had a nice solid 15 psi and then the sound of the pump changed and the pressure dropped to about 5 psi. " this has got to be the pump, no?

 

[jamnram]

Paul,



My initial thought it was the conection at the valve. I checked the conection numerous times, backed the valve out, adjusted the end piece on the gauge hose. I'm positve the gauge and connect were fine. Had left the gauge on when changing the pump and new pump had presure.

 

[dknoch]

It was the LP. After explaining things to the dealer, they replaced it under warranty. $0. 00