How do you (or someone else) test a VP44?

4x4dually

4x4dually

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Mine is acting like it did when it went out thousands of miles ago. I'm wondering if that isn't some of the cause of the bucking during cold weather with my juice box.

Is there anyway to test the outputs? Can the dealer do it? How do they do it and is it realiable? I just wanted to probe for some input.

Thanks, JWB
 
You know, I haven't even remembered to look. It just started doing it this last week. After getting to speed on the highway and pushing the pedal just enough to maintain speed, it acts like it cuts power back and forth....same crap it did last time it went out. Sucks.
 
Sounds like it's going out......try the key thing to bring up the codes and see if the death code shows up. STUPID PUMPS!
 
Ya. I'm in the wife's Yota with her today...I'll check the codes when I get home.

Is there anyway to test pressures and get actual readings? If I'm gonna replace it by God I want proof it was out....not some dumb box full of 0's and 1's telling me a code.
 
Oh I hear ya......I don't trust them numbers either. As far as testing pressures I'm not sure, I haven't heard of anyone doing it.
 
OHHH I just remembered something.....:bang .......my brothers truck acted the same way when his pump died. It'd run great for a few miles, and then it'd start surging and he'd have a hell of a time maintaining speed and the pedal got hard.
 
I can maybe help you on the diagnostics. Cummins has a few tests as far as troubleshooting goes. Really sounds like a VP timing/fueling fault though. I'll Pm some info. to you. Problem is, if its running fine other than the symptoms you've mentioned it will be tough to find anything.
 
What is your delivery pressure at under load.If it is to low it can cause the same symptoms at higher loads and engine speeds.If the delivery pressure is ok then I would check the codes for the dreaded po216.The only way that I know of to check the performance of your pump ( as far as pressures and timing function)is to run it on a pump stand.As far as the codes in the on board diagnostic system I have found them to be accurate with the symptoms.Every once and a while I come across a weird one with some wiring issues or a bad ecm but they are rare.I would also make sure your battery connections are good.I hope this helps good luck
 
Thanks guys. Delivery from the lift pump 13-14 idle and no lower than 10 WOT under load. Vulcan big line/relocation kit helped me out there. The only other time I have experienced what I feel now is before my other IP died. The lift pump had actually failed and I was running on the IP only and it killed it. Now I can see my LP pressure is always above 10 with my gauge (attitude). I'll probe around on it tonight.
 
What both of the guys above said is correct.

Getting an actual test on your pump to show a problem is tough.

The only way to be sure would be to put it on a stand. But, you symptom may not occur durring the pump test and then your in the same boat you are now.

~Wes~
 
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