I have a 1994 5.9 cummins with a 7100 pump on it i sent the pump in to have it done up and now it shakes and hesitates below 1500 rpm. the pump is supposed to have 400hp it goes pretty good when you want it to but driving around at slow speed in town and parkinglots it is a total pile of **** almost like it its only hitting on 3 cyl or something. the place i had it done is trying to say that the delivery valves on the 1994 trucks are only 12 ml so it is not delivering enough fuel but if i hammer on it the hesitation and shaking goes away totally any ideas ??? seems like it should be running out in the top end instead ..

 

Put this on the 12 valve aftermarket section, you'll better responses there

 

well you cant just say your pump is a 400 hp pump. you have if they are stock 131 DV's which deliver enough fuel for quite a bit more HP than 400. does the truck blow smoke white or black what kind of injectors do you have. hpw much boost are you running on what kind of turbo? bunches and bunches of questions

 

hi, question about hesitation, i've been having for some time now, replaced the apps sensor, still no luck, changed fuel filter, air filter, no luck.
i've hooked up a scanner, the map reads 77, and in park at idle, it says its under load?
is that leaning towards a bad map/iat sensor?
it runs fine after about 1000 rpm, if i take my foot off the pedal, and push it again, it hesitates for a good 3-4 seconds, like the engine is flooding itself out, then it goes like a bat outta hell, also, idle jumps up and down every now and then at idle and has even stalled out.
any idea's?