My uncle cooked a VP a few days ago (02 HO 6 spd 24v). No codes or anything, but just quit on him out of the blue and wouldnt start again. He had fuel at the delivery tubes. He was running a stock LP, and a cheap lil quadzilla xzillerator tuner, so i told him it was in his best interest to put an airdog system on while we were at it. I put a new HO vp in it and the airdog 100 kit yesterday in 6 hrs flat including lunch break, haha. Truck started (after some time of bleeding air) and seemed to be running fine. He called me on his was home and said that if he gets into the throttle the truck seems to be missing and running like crap. Idle and low speed seems fine. It just seems once he gets into some load that it starts "missing". Now, i havent driven it, so i cant say exactly what its doing. I told him to continue driving it, and that there is most likely still air in the system. 45 miles later, the truck is still "missing" under load and isnt getting any better. Today it started for about 15 seconds and stalled on him again, but started back up. Any ideas? His fuel pressure gauge stopped working a few weeks ago, and he said hes picking a new one up today. When i found out what his pressure is ill post it up here. Until then, any further ideas? Sound like hes sucking air from somewhere? Maybe a bad quick connect fitting on the airdog system? Thanks guys

 

Did you change fuel filter? I wouldn't drive it at all without knowing what the fp is... did you do a draw straw or anything like that? had lift pump on block and not in the tank, right?

 

Well the airdog obviously bypasses the stock filter and has the canisters so yeah new filter. It was the airdog 100 kit that uses the stock draw straw on the tank, so its the original draw straw. It had the block mounted lift pump, not in tank pump. I told him to cycle the key and see if any codes show, he got back the po500 which is speed sensor related i think, and a p1693 which im pretty sure just means that there are codes stored in the PCM that should be checked. I have a SOLUS scanner that can access all that stuff its just a matter of getting the scanner to his place an hour away. He's trying to borrow a truck so he can go out and buy a new FP gauge. Its just weird, never seen a truck buck and run like crap after it basically just had the works done to it. Could we maybe have bumped the cam sensor or something while we were in that area?

 

Any ideas anyone?

 

Throttle position sensor?

 

Would a tps make it miss and buck??

 

It could possibly cause some driveability issues like that if its miss reading and trying to find where it wants to be and causing a wondering rpm issue. If I'm not mistaken

 

I know I plugged it back in during reassembly after that new inj pump. I'm just hoping it's not a bum injection pump.

 

If you unplugged the apps, there ya go. You need to MANUALLY reset the apps (not the unplug battery trick that only resets the ecm). Do a google search, theres a good thread on how to do it on the cummins forum, it involves probing a wire with a voltmeter and setting the apps back to the setting that it calls for on the back of the apps (next to the bar code)... for example, my '00 calls for .502 volts. Give it a shot, because I was getting dead pedal and intermittent miss when my voltage dropped down to .302

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I found it for you... I know it's from another forum, but here ya go- APPS Reset procedure - Dodge Cummins Diesel Forum

 

I'll have him reset the apps. He says it's blowing white and black smoke, maybe an injector problem?