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Discussion Starter #21
It says that I have 12 volts pin to pin. But it only had it when I bump the starter. I'm contimplating just running power to a toggle switch and to the fuel pump..
 

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It should only have 12 volts for about thirty seconds when you bump the starter. It will not be at 12 volts again until the engine starts. While cranking (starter energized) it will be at some lower voltage because the ECM is putting out a pulsing voltage.

I'd suggest putting, (for testing purposes) 12volt power directly and see if the pump runs.

Some folks have done as you suggested and run a toggle switch or from a source that is energized with the ignition key in the 'RUN' position, directly to the pump. I don't recommend that because, in case of an accident, the pump will continue to run until you turn it off; this could result in a lot of diesel fuel in places you might not want it to be.
 

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You should get that voltage on the starter bump.....you must be pretty quick to grab that and read it inside the 25 second window.
Sounds like the in-tank lift pump is dead to me.
You can access it by loosening the 2 passenger side bed bolts until only a coupla threads are holding then remove the 2 driver's side bed bolts and raise the driver's side of the bed (with a coupla friends or paid help/neighbor's large football playing kids...I used my engine hoist) and stand right over the module to unlock and pull out of the tank.
 

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The lift pump is the technical name for what we've been calling the fuel pump. They are the same thing.

It was originally located on the engine block right next to the fuel filter, but, because of the many failures of that pump, a different type pump was retrofitted and integrated into the fuel tank module. This new pump supposedly put out a lower pressure but a higher volume. It also had a relay associated with it and the relay is controlled by the same wires that the ECM originally fed to the original fuel pump. This takes a major load off of the ECM.

It and the injection pump (VP44) are the only pumps associated with fuel.
 

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Discussion Starter #26
Well then I have replaced both pumps and I'm still getting no fuel.. so something with my wiring has got to be screwed up. Thank you for clarifying that for me though!
 

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Crack a banjo fitting on the intake side of the injection pump and bump the starter. If you get fuel squirting out around it the VP44 is bad. If not you have an electrical or lift pump issue. Remember you said you have a code fro a bad VP44, it is likely correct.
 

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Discussion Starter #28
I replaced the VP44 and the code went away. I already tried bleeding the system. Nothing comes out and the pump doesn't turn on..
 

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Ryan, have you tried supplying the lift pump (in the tank) with 12 volts to see if it will run on its own? That way you can isolate and just confirm you have a working lift pump. If it does run, then sounds like wirring/connections are bad OR the ecm is not commanding it to turn on. A quick way to see if ecm is booting up is that when you turn the key to the on postion (not cranking) the wait to start light on the intrument cluster should light up immediately. If it is delayed comming on or doesnt come on at all, you likely have an ecm issue. It sounds like you need to start over and recheck all your work, checking battery connections, all grounds, and by confirming the replacement parts are in working order. It is not uncommon to get parts bad out of the box. I hope you can get it figured out soon!
 

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Also do you have any current codes stored in the ecm since you have cleared them? This may also cause the ecm to not command the lift pump
 

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Discussion Starter #31
I'm gonna run power to the pump and see if it will turn on. If it doesn't I'm gonna replace another pump I guess. But if it does I'm gonna rig up a switch for the time being. And I have one code. It's for a low curcuit b to the throttle positioning sensor. But that has been there since I got the truck. I'm just gonna try the whole power thing and go from there. I know there is power to part of the pump because it still reads the fuel amount and my distance to empty.
 

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Discussion Starter #32
And I also was thinking maybe ecm but everything works as it should. All the lights come on right away. Just still kinda confused on everything but I'm gonna try the 12 volts to the pump
 

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I had "Issues" with my lift pumps. Most made by the Carter pump co, but sometimes Cummins would put their name on the unit. Personally I do not care for the "In the tank" lift pumps, as they are not readily service available.
New lift pump is a FASS, (For my 2001) manufactured especially for the VP44 pumps. Mounted it back where the original Carter units were placed. To be able to get to it, just remove the 2 hold down bolts, and gently pull aside the fuel filter, THEN you have access to it. Actually I bought 2. 1 to install, and keep one in the back under the seat. Why ? Because you never know when the thing is going to go bad, and 99% of the time, it WON'T be in your driveway !
"If" you do have problems with your Injection pump. The owner at Blue Chip Diesel REALLY know these pumps. Very knowledgeable fellow. I think his name is Chip. I bought one from him. Very happy with it. Just be careful reinstalling the pulley, that you get that little key way right over the key slot.
How do you know the little fine mesh screen that is part of the pick up unit is not plugged ?
Guess you have been there before with dropping the tank ?
Good luck !
 
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