My lift pump doesn't start until I bump my engine over. It used to pump up pressure when I turn the ignition on and before turning over the engine. What would be the problem causing this. I did replace the relay switch, but it didn't make any difference.
Thanks

 

Granted your truck is a couple of years newer than mine, but mine (1999) has always required that you bump the engine to get the lift pump to operate. In my Haynes manual it even states that you must be bump the starter in order to bleed the system after replacing the fuel filter. I don't have my book here to quote, but I'm pretty sure the instructions applied to 98.5 through 01

 

You cant fix whats normal. Every dodge with a cummins that I have seen including my own all need the starter bumped before the pump will run.

 

Come , come, now. the pump should run for couple seconds as you go to ignition run and then shut off. It will not do this againt until some time elaspes. It should go to run when you go bump start and run for 25 seconds or so. It will repeat the bump run.

 

Dozer has it correct it should run for only a couple of seconds when you key it up (on position - not crank) the first time to prime the system that would be normal.

Do you have a fuel pressure gauge on the truck ? Is it at zero before you turn the key to the on position ?

 

Yep this is the way it used to do, but now I don't hear the pump run until I bump the engine. Then and only then does my gauge move. The tech at the dealer was questioning this also, telling me that it should run when ignition is turn on.

 

NOTE: THE TRANSFER PUMP WILL RUN LESS THAN 2 SECONDS (VARIES WITH ECU CALIBRATION) WHEN THE IGNITION KEY IS FIRST TURNED TO ON. WHEN THE STARTER IS BUMPED (DO NOT ALLOW THE ENGINE TO START), THE TRANSFER PUMP WILL RUN 25 SECONDS. IF THE ENGINE HAS BEEN RUNNING, THE IGNITION KEY MUST BE CYCLED TO ALLOW THE TRANSFER PUMP TO RUN.

Read the article. Like I said you cant fix whats normal and for what its worth you had better consult with a tech that knows whats correct.

http://www.dodgeram.info/tsb/2003/14-002-03.htm

 

All my lift pump does is a half second "grunt" when I turn the keyswitch On and the engine starts faster than any of the gassers in my yard.

 

Yes that little grunt would be normal the only reason i could see he would not have it would be a failure in the PCM seems unlikely that it would act normal otherwise though.

 

Well, don't know if I just going deaf or what, but after reading the response to my first post, I got down as close as I could and push in the light button on the door jam to stop the dinging and turn the switch on. Sure enough I could hear the pump do a short grunt. But since my fuel is draining out of my filter housing back to the tank somehow there is no pressure until I bump the engine and let the lp run for about 15 sec.
Just wish I new how the fuel is leaking out and it's not leaking out on the ground so it's got to be going back to the tank.
Thanks for your help guys and gals to if any....

 

mine was doing the same thing it was a o-ring on the cross over tubes. It was damp under one of the injector lines so I pulled that tube and the o-ring was cut in two.

 

Uhhhh, help this ole dog out a little bit...What is the cross over tubes and where located? Are you talking about the injector lines?
Thanks

 

If you pull off the injection line at the injector there is a tube that has a o-ring on it for a seal. Check for dampness under the injector line where it screws into the head. After you remove the line take a small screwdriver and gently pry on the injector crossover tube it will come right out.

 

Well, I found my problem. It was the T at the back. The return line from the IP was loose, turned it nearly a full turn. Now my pressure stays up and when I turn the switch on now it goes up to 5 lbs. after the lift pump grunts.