1998 N14 cummins stumble upon acceleration

Thanks for your replys. Yes my temperature did increase enough that it is on par with the others. However still have the same problem. Found a small pinhole in my fuel return line and replaced that. Still doing same thing. It's not severe but still bothers me. Only does it while going up thru the gears. If I lug it down just to check it when I get back in the throttle it picks right back up like it's supposed to.It's like the truck knows when I'm upshifting as opposed to downshifting. I'm driving it but it's driving me crazy! I did replace a couple O-rings on some fuel lines. May have helped some but won't know til I get under a load with it. Thanks again.

 

Thanks Heavyd. Looks like that is gonna be my next step.took a short run with it on Thurs and Friday. Seems like the idle is getting a little rougher, still stumbling a bit on acceleration goin up thru the gears, but runs great on the interstate. Intermitant problems are always the worst to solve. I did get 3 extra sets of o-rings for this very reason. Maybe the idle is affected enough now that I can start pulling injector wires and see which one doesn't make any difference. Thanks again to everyone,Mike.

 

Thanks for the responses. Thought about the camshaft myself. Trying to pretend it ain't that. Checked the ECM plate. Took it off and blew air thru it. No blockages or pinholes that I could see. Changed some o-rings. Gonna start swapping injectors and replace the pass-thru connectors and see if that helps. Then I'm gonna pull what little hair I've got left outta my head. Maybe replace some sensors cause I don't know when any were last replaced. Engine has 1.3 million on it so who knows. Thanks again.

 

Just an update on this. I finally got the problem fixed by replacing injectors. I had bought two Cummins recons. Was gonna use one for a spare on the road but wound up using it now. I did like Heavyd suggested, but replaced two at a time instead of one in each head. Saved some time but probably wasted a good injector. Just reused the ones that I found were good
(with new o-rings). Thanks again for all of your ideas.