Hey folks, I have had this similar issue before and I am really about ready to throw this **** truck in the junk pile, its a HEADACHE! anyways I have a very noticeable engine skip/miss ranging anywhere from 1800-2300 rpm occurs in 4th and 5th gear under load/acceleration and seems to be low on power. Now the things I have done to try to remedy this problem are as follows: truck is equipped with a timbo apps, cleaned mapp and iat sensors, disconnected batteries and did the reset apps procedure, I checked the voltage range for the apps and its good. now just tonight I noticed the rpm guage not going up smoothly while leaning into the pedal its more of an irrattic or "skippy" rise in rpms but the motor sounds fine. WHAT IN THE WIDE WORLD OF SPORTS IS THE PROBLEM!!
Please Help....your help is much appreciated!
Semper Fi

 

What is your fuel pressure? Sounds like maybe the VP is thinking about quitting. Have you checked for codes?

Rick

 

No codes

 

No fuel pressure gauge

 

Sounds like the time when the engine is calling for the most fuel it isn't getting it.
I agree first thing to look at is fuel pressure between the filter and the injector pump. Make sure it is getting all the go juice it needs. My first problem I ever had with my truck was because of a plugged filter, It acted just like you describe. Could be a lot of things, collapsing fuel lines, shot lift pump, plugged filter, clogged pickup in the tank....
If your pressure is good next step would be that the individual injectors might be slightly clogged. That would let them work fine at light load but not have enogh pressure at the nozzle at wide open to spray a good mist.
Could even be an injector nozzle just going bad, if the coils are tired then the long open and fast cycling could be an issue.
I wouldn't think it would be a exhaust restriction because although it would also lose power at top end it would be a smooth loss not an intermittent drop.