Engine/Transmission (1998.5 - 2002) Odd Engine Stumble Issue

[LRotter]

Hey guys, I recently discovered an interesting problem with my truck(see sig). I was driving down the road Friday evening, cruise control set at about 75mph when I had to hit the brakes. I went to accelerate again and the engine seemed to stumble. RPMs went down a little and the truck would not accelerate. I pushed the pedal all the way down and nothing, it just sat there at about 2000 rpms and would not take off. All of the sudden, it took off like a shot. I drove down the road a little farther and it did it again. After about 1/2hr, it hadn't done it again so I put the cruise back on. Had to shut off cruise and tried to accelerate, again with the stumble. Turned cruise off and never had the problem again for the rest of the trip(about 30 more miles). I checked codes and the only thing I had was p-0500. Driving back home Sunday morning(about 120miles) I did not use the cruise control and never had the stumble, truck ran fine. This seems very odd to me. I don't use the cruise often but this issue seems to be linked to usage of the cruise control. It almost seems like the truck is running out of fuel but then comes back on. I'm hoping this isn't an issue with the VP-44 but I'm afraid it might be. Anyone have any ideas?



T. I. A.

 

[nps]

Has your spedo been erratic? Sounds like the problem is with cruise control only. You may loose your spedo and ABS soon. Get ready to change the sensor out.

 

[LRotter]

I haven't noticed the speedo being erratic. I do think you are right and it's something to do with the cruise control since this only happens after I've had cruise on. Seems odd that it would do this with the cruise off though. But, as I said, it only happens after I've had the cruise on. I can't imagine what else it would be though. Do you know where that sensor is? I hate to even ask but how much does that sensor cost?

 

[nps]

The sensor is on top of the rear axle. Can't give you a cost. Not surprising that it is tied to cruise control - you hit resume and the computer is looking for a speed input that isn't there. So it just sits and thinks. Without CC, the command comes from the APPS via your foot.

 

[SnoKing]

I have heard that spinning your tires will set a 0500 code. SNOKING

 

[LRotter]

The thing is, when it does the "stumble", cruise control is totally off and I'm just using the ol "right foot as cruise control" method. Again though, it only does this after I've been running with the cruise on. So, cruise on, cruise off, right foot on foot feed, try to accelerate, engine "stumbles" for several seconds then it takes off. That is the sequence of events. Sorry if that wasn't clear before.

 

[nps]

Resetting the APPS is free - may want to try it before spending other $. Perhaps since the APPS has been at the idle position with the CC controlling the throttle, there is some 'confusion' when it comes back into play.

 

[LRotter]

Ok, I might try that. Now, my next question: I probably should know by now but how does one go about resetting the APPS? I know, I know, you can kick me later. Thanks for the help though.

 

[nps]

Read this thread here . Page 1 has both procedures detailed and discussion on the merits. You decide which one to perform.

 

[TNowak]

Hey guys, I recently discovered an interesting problem with my truck(see sig). I was driving down the road Friday evening, cruise control set at about 75mph when I had to hit the brakes. I went to accelerate again and the engine seemed to stumble. RPMs went down a little and the truck would not accelerate. I pushed the pedal all the way down and nothing, it just sat there at about 2000 rpms and would not take off. All of the sudden, it took off like a shot. I drove down the road a little farther and it did it again. After about 1/2hr, it hadn't done it again so I put the cruise back on. Had to shut off cruise and tried to accelerate, again with the stumble. Turned cruise off and never had the problem again for the rest of the trip(about 30 more miles). I checked codes and the only thing I had was p-0500. Driving back home Sunday morning(about 120miles) I did not use the cruise control and never had the stumble, truck ran fine. This seems very odd to me. I don't use the cruise often but this issue seems to be linked to usage of the cruise control. It almost seems like the truck is running out of fuel but then comes back on. I'm hoping this isn't an issue with the VP-44 but I'm afraid it might be. Anyone have any ideas?



T. I. A.

I had a similar problem with my 02. When it was cold it acted up the same way. If I let it warm in my heated garage it ran excellent. I replace the VP44 fuel pump and fuel filter which I purchased directly from cummins. Usually it is colder at night like when you left friday, than it would be in the morning like on sunday. My pump went at 80k. You will know if it is your pump if you replace your fuel filter and it won't start. They just get weak over time and will eventually burn up your injector pump which is a costly repair.

 

[nps]

... I replace the VP44 fuel pump and fuel filter which I purchased directly from cummins... . You will know if it is your pump if you replace your fuel filter and it won't start. They just get weak over time and will eventually burn up your injector pump which is a costly repair.

The VP44 is the injection pump. I think you are talking about the lift pump.

 

[TNowak]

Yes, that is what I meant. thanks

 

[Silver_Ram]

LRotter,



You are describing almost exactly what happened when my VP44 was dying at 44,000 miles, except for the P500 code. I took it the dealer, I don't think it had any codes & they replaced it under warranty.

 

[LRotter]

Well guys, I have an update. I haven't had time to try resetting the APPS but I did decide that I would check for codes today during lunch even though the truck hasn't acted up since the Friday before I started this post. I wish I wouldn't have done that. Of course, I found the dreaded 0216 code. So, I guess I'll be getting a new VP-44 soon. The wife is going to love this. In the past 6 months, I've put new wheels on, fixed the Vacuum pump/PS pump seal and put a FASS-150 on. I may call the dealer and see what they can do for me but I'm sure they won't cover it under warranty, even though none of my mods made the VP to fail. I don't really trust the dealer that much though. So, I'll probaby go to my local diesel shop. Since I'm going to need the new pump, is it worth going with a HRVP-44? From what I have heard, the price is about the same and I'd get more power from the HRVP-44. My question is this: Is the HRVP-44 any more reliable than the stock VP-44? While I would enjoy the extra power, I would rather have the more reliable pump.



This sucks but I guess it could be worse, I could have bought a Ford or Chevy.

 

[nps]

Pull off your EZ and take it to the dealer if you have less than 100K miles. I don't know if a HRVP is any more or less reliable than a standard VP, but the standard costs $1000 and the HR is $1600. Think I'd tell the wife I need a HR, but buy a standard and a Smarty with the money. :-laf

 

[surfbeetle]

It should be covered under warranty if the mileage is still under the limit. Its worth a try. You may just find a dealer who doesn't care about the mods. The VP44 has a known history of failure so one would think that dealers would be used to changing them by now.