I have a 2001 Dodge Ram 2500 with VP-44 IP. At the time I got the truck it was already experiencing intermittent dead pedal, and Initially there were 2 codes, P0382 Glow plug/heater circuit B, and P0112 intake air temp circuit. I found a loose connection on the relay of circuit B (2) and cleaned the IAT, which was heavily carboned. Neither of these codes have returned, with the truck having at least 150 start cycles, and having driven over 800 miles since reset. I ordered a fuel pressure gauge from Geno's Garage, and found that the lift pump was only producing 6 psi at idle and 3-4 psi WOT.
I have since replaced the factory fuel pump with a FASS DDRP purchased from Summit, and now have good pressures. I at first measured pressures at the output of the fuel pump (B4 the filter) and had pressures around 18 psi at idle, and 15 WOT under load. I moved the gauge from the fuel filter, to the schrader valve on the IP. Pressure are 15 psi @ idle 13 psi WOT unloaded, 10 psi WOT under load. When the truck went dead pedal, pressure was about 13 psi, and rose to 15 psi before the engine resumed supplying power. This truck though it only has 89,000 had no maintenance for the past three years, other than additives being added to the fuel. The previous had interesting ideas on additive mixtures. often adding other refined oils to his fuel mixtures.

Is there any way I can test the IP or APPS, other than just throwing new parts at this truck in order to diagnose the remaining problems?

 

For those who have been reading my post, I reset the AAPS this morning using the procedure found on "The Diesel Truck Site". Posted by the Administrator of that site.
Resetting the APPS on your 24 valve Dodge Cummins, causes the ECM to 're-learn' where the throttle is at all times when something happens to cause the ECM to not understand what the APPS is telling it like a dirty spot or something like that.

What you do is disconnect BOTH batteries (yes you will need to reprogram your radio), turn the key on and wait for at least 10 minutes, then turn the key off and hook up the batteries.

Once that is done turn the key on but don't start it yet. SLOWLY and steadily push the throttle to the floor and SLOWLY and steadily release it. Turn the key off and then you can start it. You have now re-set the APPS. Normally when you need to do this your APPS is in the process of failing but you bought some more time for it.

I have taken the truck for a couple of long drives with multiple start cycles.
Thus far all is good.

Thanks for reading my post, will let you know how things turn out