VP44 Bad Or Dead Pedal??
 

My buddy John's 02 CTD is having problems. It has 110,000 miles on it. It always starts easily warm or cold. His truck started "falling off" intermittently while driving down the road. Someone told him that the lift pump was the culprit, so he spent $$ on a FASS unit. (we never checked the stock lift pump) Still, the truck would be going down the road (sometimes for several hours) and would suddenly drop to an idle. Sometimes, John would downshift his auto and the truck would simply take off again. I suggested B20 (ULSD was what I suspected was causing most failures out here) so he did. Truck runs much better, but still occasionally "idles down". He was pulling his 12,000lb excavator last month, and went 300 miles without any trouble. Then, at the top of a hill, it does the idle thing again.....Is this the "DEAD PEDAL" I keep reading about?? It doesn't seem logical that a rotary pump that is damaged could still perform well most of the time, and then intermittently (and briefly) crap out. Does anyone have any ideas before John drops $1300 on a new pump??

it doesnt sound like the vp but ya never know, did you see the post about how to reset your apps you could try that, you also need to check for codes those vp's are really sensitive so it could be that

Sounds to me to be more of a tranny problem. Sounds like the tranny is goin into limp mode. Don't know enough about auto's to tell you much about the why or how's but this is exactly what they do. I had an auto for a few months that kept doin this and i would have to shut the truck off and it would take right off when I re-started it. That truck didn't last long.

Welcome to the site, hope to see a lot of ya here.:c:

never thought of the tranny, i would still say check the codes and see what comes up that may give you the most insite into this and also help us help you a little better

Have you scanned the truck for codes?

Thanks for all of the replys.....

The "check engine" light never comes on, so I assumed that there's no codes. Initially, John took it to a local dealer who sold him the lift pump and the dealer :booo:told him that the VP was probably toast. Not sure if the dealer hooked it up to a scanner......Then again, this is the same dealer who can't seem to find an AC leak two years (and $600) running.

My PPE Xcellerator (for my 06 CTD Megacab) reads codes, maybe it will work on Johns???

I dont know for sure - but it should also be OBD 2 so I would think so. If not, try taking it by Autozone - they will usually read them for free.

The Check Engine Light doesnt necessarily come on.

Let us know what you find.

If the dealer said the LP was dead - its possible that the VP-44 may have been damaged. As well, sometimes they die without throwing a code - but that would be a fairly rare occurance.

If this was a fueling problem it would be an extreme case of bad VP or LP and there would be other very noticable symptoms to go along with the dead pedal. This is either one of the sensors bad or dirty, or the tranny going into limp mode for whatever the reason.

When I had my auto for the few months it went back to the dealer several times because it would just all the sudden default into idle mode. I'd shut the truck off and start it back up and it would drive just fine until the next time it did it. Dealer never could find any problem with it or codes so they said they couldn't do anything with it. I told em I couldn't do anything with it either and my lawyer made a phone call andgot me out of the sales contract somehow. This was in one of those nasty ole Hemi's, but they run the same tranny.

Forgot to mention that fuel mileage is real good, ranging from 19-23mpg.

Truck has never died or stalled, just returned to idle. It runs great with the exception of the "idle down" events.

Also forgot to mention that we live on the Oregon Coast.....Salty air. Could this be having an effect on electronics??

it could very well have something to do with it, i would try your programer to see if you can read the codes like stated above sometimes the check engine light will not come on but it will have some stored codes.