99 C3500 7.4l cutting out under low throttle

[Brian 1999]

Hello everyone. I'm having a time trying to figure out why my truck is cutting out under load under very low acceleration. Truck idles fine and once about about 1700 rpms it pulls fine. Just when you are on a flat road and just barely have your foot on the gas to maintain a constant speed is when it cuts out and jerks back and forth. Not violently either.  Truck will not throw a code at all. Used a snap on scanner and no stored codes either. 

Parts I have replaced-

Upper and lower intake gaskets, TPS, EGR valve, Ignition control module, distributor, cap rotor and new plugs and wires. New MAF sensor, new fuel pressure regulator. New fuel pump and fuel filter. No water in the fuel. Cats were deleted after the tune I had put on it. Truck ran perfect for 3 months after the tune as well. Tested injectors and did a leak down test and they all were identical. New crankshaft position sensor too. I only run premium fuel. Truck starts fine, idles fine at any temp. Runs great at highway speeds. Any info would be appreciated. Bout to pull my hair out or go broke first over this damn thing. 

[CamGTP]

Use that scan tool to watch the live data when it happens.

 

Watch what the TPS does, MAP and MAF sensor. If any of those just cut away or change wildly at random it could be one of those.

[Brian 1999]

The only one not replaced is the map sensor. But will try that.