rebob82

I have checked the codes using the key on/off/on/off/on procedure, but they were also read at Autozone. I have a stock lift pump, probably original as the truck only has 78,000 miles. I just recently changed the fuel filter so I don't think that's the problem. If the LP pressures are really too low maybe that has caused damage to the VP44. Until just the other day we had a slide in truck camper in it that went everywhere with us. We use the truck to haul our three horse aluminum trailer, usually loaded with two horses plus all the associated equipment, so we have a pretty decent load most of the time.

I've gotten this code recently on my 2001 Dodge Ram 3500 4x4 with the Cummins 5.9l diesel. At first I thought it was the APPS as I was getting the dreaded dead pedal syndrome with no other symptoms, but it has progressed to having a little chugging or missing at highway speed under heavy load. Mostly I get a completely dead pedal when first starting out and cold, but then it will usually clear and begin running fine. I've confirmed the APPS is fine with an analog voltmeter hooked up while I am driving; the voltage change is smooth and continuous even when I am not getting any actual throttle response. I've also confirmed the lift pump is fine by hooking up a pressure gauge I can read while driving. I get 15psi at idle and usually 10 or more while driving.I'm afraid the VP44 is going or the circuit board in it but I don't know how to check it further or what else to eliminate. I talked to an instructor of diesel mechanics at a technical school who thought it likely was the crankshaft position sensor but I am not getting any error codes related to that so I'm not thinking that is too likely.I just recently changed the fuel filter. Could I have messed that up somehow and caused this problerm?Any further diagnostic help would really be appreciated!Bob