I sent my truck into the shop to get high idle set on it and it started to act weird. It recently has thrown a code while my brother has been driving and cuts out. Its a communition between vp and something I cant remember nor have the code number on hand. I had a holley blue on and eliminated it thinking it was the problem it is still acting up. Under hard acceleration and cruising it will die out and usually catch idle if not shut off. Im guessing the vp44 is going out or the lift pump what test can I do to check and pinpoint the problem. I dont have a fuel pressure gauge on hand. Thank you for future advice.

---------- Post added at 09:19 PM ---------- Previous post was at 09:13 PM ----------

My brother was saying it was slow or no communication between the vp44 and 511 or something not sure. Didnt know if that would help any.

P1689 and P0500... (betting...) P1689 is a communication error and the P0500 is ABS code (tire spin)... http://mopar.mopar1973man.com/cummins/2ndgen24v/vp44-replace/vp44-error.htm (Basically a death code for the VP44) http://mopar.mopar1973man.com/cummins/2ndgen24v/abs/abs.htm (Bottom of the page) As for the P1689 its cause from poor fuel pressure. When fuel pressure falls below 14 PSI the overflow vavle closes so the only flow of fuel is through the pump. So if you coasting for long periods of time with pressure below 14 PSI it will overheat the electronics and wear the parts internally because there still spinning creating heat and the fuel isn't moving. So hence the electronics start to take on heat damage. What I was getting at is there is only to outlets for fuel to leave the pump either by injection or the overflow valve. so if you coasting for long distances the injectors are NOT firing. (Outlet #1 closed) and if you fuel pressure is below 14 PSI the overflow vavle is closed (outlet #2 closed) so ho can a VP44 stay cooled and lubed? All I can say is to add 2 cycle oil to the fuel and keep your fuel pressure above 14 PSI. Most of us have moved up to a Raptor, AirDog or FASS fuel system that moves better than 100 GPH worth of fuel at 15-20 PSI normally. This insures the VP44 stays cooled and lubed properly.

I will get my scan tool and check it and also try get a fuel pressure gauge hooked up. I figured it was going to be low pressure and the vp about to go. Thanks for the advice I will try check it out as soon as I ca. I just dont have money for a vp so I guess she will sit for awhile. Thanks again mopar

Sad but true... A $40 fuel pressure gauge could of saved you from this mess...