Hesitation?

[JRMora]

First and foremost I have done a search on this but didn't find another problem just like mine, so here goes:



I have an '04 (305 hp) 3500 with about 105k miles on it and recently started having this problem:



When I am accelerating from a stop or accelerating from a constant speed the truck just won't accelerate right away - there is some hesitation and then it suddenly takes off if I keep pushing on the accelerator. Boost will not build either. Now, it only does this if the Quadzilla is switched "off". If it is "on" (30, 60 or 100 hp settings) I don't have this problem. The Lift pump was replaced new @ 70k, I have put in a new fuel filter, and run PS with every tank.



This is not an "every time I accelerate" problem, but an every now and then.



I previously had a BD low fuel pressure light installed but it crapped out about a month ago and haven't replaced it yet. But I can get plenty of zoom if the box is switched on, so I think i am getting plenty of fuel. If it is hesitating and I throw the switch on the box it immediately takes off.



You can see what I have installed in my profile.



Any ideas?



Thx.

 

[GaryOwen]

I am thinking the Quadzilla is somehow interfering with the APPS when it is in the OFF position. I would try removing the Quadzilla and see if you still have the problem.