Engine/Transmission (1998.5 - 2002) Miss,flutter at an idle...

[FFutch]

O. K. guys here's a good one for all you 24 valve gurus. I was talking with a guy last night who's got a 99 like mine,except 6 speed. When he's sitting around at an idle he's got a slight miss. It sounds to me like an injector. Weird thing is it gets worse when he turns his a. c. off. What do you guys think?injector?V. P. 44?He said he just had his lift pump replaced at 210k. He also said it's been doing this since almost new. He's had it to D. C. and Cummins and they can't seem to find it. I've still got my stock injectors with only 50k on them. I'm thinking about swapping them out and seeing if it fixes it. His fuel filter has been changed recently and he's running a k&n. I'll also check his fuel pressure. Anything else??All help appreciated... Doug

 

[lsenus]

It sounds like a cracked/bad/misformed injector tip.

 

[Tomeygun]

thats EXACTLY what mine does, less when cold though



its like a stumble, but truck runs fine with the pedal down...



i only have 1000 miles or so though, and service manager would do anything till i hit a couple thousand, like its going to fix it self,



mechanic buddies have said either a bad injector or seal around injector

 

[thendrex]

misfire

My truck just started doing that with 140k on it. But here's the thing, it's never done it until I got my new injection pump about 2 months ago. And I've also noticed the miss at highway speeds and it scares the heck out of me thinking it's going to stall! Anyone with any info on this will be appreciated!

 

[lberch]

Guys I had the same exact problem.



It turned out to be slimy biological crap covering my fuel tank pickup (membrane).



I did alot maintenance and troubleshooting trying to isolate and identify the problem (injectors, filters, sensors, check valves)...



I would recommend a heavy biocide and fuel addative (standyne) to start. If that clears up or minimizes the problem it will save you alot of money and time.



If you want to read more about what I went through, just do a search for posts under my name (I am not savvy enough to link you right to them)



LB