Engine/Transmission (1998.5 - 2002) Engine stumble?

[Rattler]

Need some ideas. Lately when i am accelerating the truck seems to have a mild stumble from about 2000 rpm on up. The fuel pressure never drops below 13 p. s. i. , and boost looks good. I am wondering if the T. P. S. is going?Thanks for any help,Randy

 

[Amianthus]

Mine has one too. I've just learned to live with it until I can monkey with it later. It's really pronouonced with large injectors. I've been told it's a cross firing of signals through the VP-44. Or at least a distortion of them. Either way, it doesn't seem to hurt it any, just annoying. BTW, I've had it for the last 20kmi.



Now if I can just get past this lift pump situation.

 

[rholcom2]

I dont know if this is what you are describing, but. My 98. 5 will... ... . skip, burp, coughs, or miss out, how ever you would like to explain it. When it does it, it is in the same RPM range as you are describing, right around 2500. When it does this it will shoot out a large ammount of white smoke, and makes a heck of a racket. Talked to the dealer about it, and he seems to think if the service engine light doesnt come on, it is a fuel problem. If a light would come on, it would indicate a problem with the pump. With my problem he told me to be sure to buy fuel at a "high flow" fuel station, and use a product such as Stanedyne. I have tried fuel treatments, and still, ever so often it will occur, not predictable at all.

 

[stevek]

I had the same thing and a new fuel filter solved the stumble to a large degree...

 

[Amianthus]

RHolcomb, I would guess that your VP took a hit. When it belches white smoke and a miss (with good fuel pressure) it can mean that the VP is on it's way out. Now it could be bad fuel, but that would manifest itself all the time, not just at higher RPM's.

Fuel filters have no effect on this problem. Trust me.

 

[2-ND TIME]

engine bucking

Mine does this and it is really annoying. Mine is much more pronounced at the lower RPM . Chrysler had another go at it and only found that the valves were out. The last time that the valves were done didn't help either. They changed the fuel with only 2 , 2. 5 lbs loss across the filter and air filter again and I dought if this will help!!!!!!!!!!! Have it booked in to Cummins soon hope that they can find the problem. Does anyone know about the advancing of the timing with the solonid in the VP-44 pump.

 

[GTX]

RHolcomb, Amianthus is right. What you are describing sounds exactly like the way my first VP44 died. Puking white smoke when it was missing, stumbling under a load. There will not be a check engine light on, but there may be 2 codes, a 1693 and 0216. I am not sure if the 0216 code is right, that was a long time ago, it should be close. Go to the dealer and request that they scan it for codes and see if there are any.