VP-44 Going Bad?

[heliopilot]

On one of my 1999 trucks has an problem. It has a rough idle(sort of like a gas motor with a bad plug or wire). It is only noticable at idle after pulling a long uphill grade or when loaded. (the symptom only happens at idle). no power loss is noticed at speed, the truck has good lift pump pressure(it's been replaced once), tank full or empty no differance,and filter clean. Anyone else with these symptoms? Is this a Vp-44 pump slowly failing?

 

[Steve Campbell]

Could be as you suggest or...

Entrained air in the fuel from a number of factors. Warm fuel, bad location for lift pump, etc.

 

[Shooter]

some one else had the same problem. Search as dead as my lift pump so all I can tell you is YOU ARE NOT ALONE.

 

[csevers]

Me too

I too have a slight miss at idle but it is not all the time and I have not been able to pin it down to any thing or time but seems more when i use cetane boost from A oil I sure as hell hope this is not a precurser to future pump problems I don't carry that much cash around to to throw down on new pump after warrenty runs out in about 34k.

 

[heliopilot]

Who else is having these symptoms? and what have you tried as a solution? thanks

 

[claymike]

I had a hard intermittent miss at idle. Did not have any power loss, ran good other than at idle. Had it to the stealership and to Cummins but they could not find the problem because it did not throw any codes. That’s another story. I went home and put on a new fuel filter although the old filter only had 1,000 miles on it. I also added some Premium Plus injector cleaner from Cummins. The miss has been gone for over 1,500 miles now.



Mike