Engine/Transmission (1998.5 - 2002) VP44 Pump HELP!!!!

[waltmoe]

I just helped my friend install a very good quality VP44 rebuild in his 2002 2500 ram. We took our time and installed this pump by the numbers, all went well. When we attempted to start the process of bleeding the fuel lines the OEM FASS pump does not work, we just installed this new pump about 3 weeks ago. We were very careful with the entire install process, we are both very experienced shade tree mechanics. .



Does anyone have any idea what the lift pump would suddenly does not work, this does not make sense.....



Any assistance and direction would be appreciated.



Thanks

 

[Bob4x4]

Did you try bumping the key or did you just try cranking?

 

[waltmoe]

We turned the key to ignition then bumped the starter to start the pump.....

 

[AEdelheit]

First thing I would do is put a volt meter on the plug going into the FASS and see if you have power, if you do it's the pump itself, if you don't it's on the truck side

 

[waltmoe]

Thanks... . We did do that and we are getting some low voltage, we are going to double check it again. If there is confirmed low voltage do you have any idea what would suddenly cause this low voltage... Thanks for the help and response to this post.....

 

[Bob4x4]

If you are using the oEm wiring and not a relay system the ECM is a pulse width modulated signal not batt voltage it will always be less than charging voltage