Engine/Transmission (1998.5 - 2002) Fuel Pressure Gone! Help

[klaybus]

15 days ago +- I installed Westach FP Gauge. Upon completion of FP Gauge I noticed low FP.

Took truck to dealer for new Lift Pump & it was covered under the Cummins Warranty. This

morning on the way to work I noticed my FP was running around 15-16 PSI, a little higher

than normal for cruising... . Typically around 13 PSI+-.



After work today got in truck & truck was running like starved for fuel... Looked at gauge

& had 1-3 PSI. Limped truck home & went to the dealer & he said likelihood of LP going

bad in 15 days after being replaced with new model LP was low. Took truck home & replaced

fuel filter (looked OK) & now while trying to get my lift pump to cycle I get nothing. I

can't even get the lift pump to cycle... . Sounds like lift pump to me I guess!

Has anyone had this problem before? Is there a fuse for the lift pump?

Planned on taking my truck into Dynamite Diesel Technology tomorrow to get dyno ed, but

not looking Good at this point.

FP gauge is mounted on the discharge side of the filter.



Thanks, Clay

 

[JR2]

It very well could have failed. I thing I would check to make sure the wire harness is still attached to it and then either run to cummins to get a new one or make an appoitment with the dealer.



John

 

[Briar Hopper]

"Likelihood of new lift pump going bad in 15 days after being replaced... is low..... " NOT SO. It can and does happen. I've bought new ones, both for myself and for customers, that were installed, immediately or even shortly after, found to be defective, and had to go through the old Remove, Replace, Return routine.

The new stock pumps are supposed to be better, but that doesn't mean a few bad ones don't sneak into the bunch. The last ones I bought 3 weeks ago were still carrying the Cummins part number of 3990105.

 

[klaybus]

Fuel Pressure gone

Briar,

How do I check to see if the Lift Pump is getting power? I was told that the LP is powered through a relay by the ECM... . Is that true & how could I check to see if it's getting power?



Thanks, Clay

 

[Briar Hopper]

Clay, got a volt-ohm meter? Ya know, an electrical tester? Or even a little cheap 12 volt tester from AutoZone will do...

If you reach under the fuel filter canister with your right arm, you'll be able to feel the lift pump. Feel along it, to the bottom of the pump, there's your electrical connection clip. Squeeze the clip and pull, it'll come free.

You can have a friend or family member turn the key on while you use the tester to check for voltage at that clip.

Maybe you'll even find the dealer left the clip connection loose, didn't firmly connect it. Small possibility.

I doubt you have an electrical problem, but then again, you never know. They SHOULD cover it even if it's electrical. If they give you a hassle, find another dealer.

 

[RobbyRam]

I had my truck in for the replace of the lift pump but it was not done at the time they said it would be, so I called the dealer and they told me that the one they installed was 'bad' so it would be another day. The new one (3rd one) I have now is fine.

 

[klaybus]

Problem Discovered??

Briar,

While I was checking for voltage in the wiring to the LP, it lit up my test light. I checked the connections at the LP & at the other end of the patch cord & re-plugged it in. Whoola..... The LP started running. I got the truck re-primed due to changing the fuel filter & she started right up. Ran up to dealer to buy the patch cord that powers the LP & they stated that they don't sell it, & it only comes with the LP. After arguing a bit with the service manager (Which changed my opinion on him a bit ) he opted to dump it in the parts managers lap which gave me a replacement cord under warranty.

I want to thank everyone that helped & send a special thanks to SIXPACK & KCOOK for the help! I was about to jump off my roof with the thought of my truck being down until mid week when the dealer could get me in. Kcook was at my house & Sixpack came over to help.

Seems to be running right now. Hopefully solved the problem with the new cord...



Clay