I'm starting to run out of things to clean/replace on this thing, short of ripping the engine out. Problem - at low RPM's (800-1300) I have a stumbling issue. It is most noticeable when I take off from a stop at light throttle. It will nose over, then come out of it quickly. If I push through it with a heavier throttle, then the problem is not there...only if I am in that RPM range it will stumble. And it's a steady stumble, kind of cyclical. If I sit there and brake torque it up to those RPM's, the truck will come in and out of this stumble...like I am pushing the gas pedal down and back up again...hard to explain. Plugs, wires, cap, rotor, injectors, throttle body cleaned, MAP sensor replaced. What am I missing? I'm tired of throwing money at it.