I will test the cruise control and see if that makes it surge as well.

 

read this

http://www.bluechipdiesel.com/vp44diagnostichelp.html

 

I just read that Nickg.
Thanks!
From what I read a flat spot in the RPM band could be the APPS.
It doesn't seem like Dead pedal.
When it is fish pulling, usually at light throttle input, I can blip the throttle and it has good power and super smooth.
I did the key trick and got
P PCU
and
P ECU.

 

I put it on my friends sacnner today.
No codes, but I did notice that the engine sounded like it was under load or the timing was changing when the inj. pump fuel shut off was toggling from on to off...?
And the load value was also changing from 0 to 4..
Sound familliar to anyone?
Thanks

 

that will happen when the grids cycle or the AC cycles (ac cycles anytime you have the selector in defrost)

also if you have a failing apps it will 99.99999% of the time trigger a APPs code, might be best to call Bluechip, and explain your symptoms, if you need an apps do a search for TIMBO he sells a more robust williams switch thats plug and play , for 160$ delivered to your door, around here at the dealer that same part cost 800$ canadian

 

I can see the A/C cycling changing the load value and adding a load to the motor as I had it on defrost.
But, what is up with the line on the scanner labeled -
INJ. Pump Fuel Shut Off -that was togling between on and off on the scanner?

 

Did you get this figured out?

 

Nope, it still fish tugs, but only at 15-25% throttle -as read off my Edge juice monitor.
I am thinking Apps as it only happens in the same throttle input level..