1995 K2500 454 rough start up and very low power when accelerating . Runs fine when barely feathering the throttle but if you need the power for any reason its just not there. Floor it and it will hesitate, and then slowly, very slowly begin to accelerate. Plus when in park, and trying to rev the engine it will miss like its trying to govern itself out.

SOURCE: Synchronization problem between accelerator and transmission at low/no speed

disconnect the egr valve and try it at low speed if you give some gas egr open to mush to mush air not enought gas create hesitation before changing the egr just disconnect it and try hope it FIXYA our problem thanks pierre

SOURCE: Rough idle, Car shakes, sputters and misfires upon acceleration

It sounds like you may have a problem feeding the fuel to your engine, I had the same problem with my 89 RS. All the 1989 model's fuel systems were recalled. I think you may need a new fuel pump. The fuel pump is located inside the gas tank in the rear of the car right under the rear axle. The fuel pump itself isn't too expensive, but with other small parts such as the electrical harness upgrade and fuel filter and the labor you should be looking somewhere in the $500 range. I hope this helps.

SOURCE: after bout 45min it stops accelerating

Change your dist. cap heat exspanion crack{ crack closed when cool opens when hot, jumps sparks
inside the cap. remember your fireing order write it down see ya.
leroy

SOURCE: hesitation , skipping,engine cuts out when accelerating

Bad coil they breakdown when the engine get hot. There is 3 coils total when it starts missing start pulling plu wires until you find the one that is not firing

SOURCE: engine wont go over 3000 rpm while driving

Is the check engine light on? If so check what codes are stored. It sounds like the m a p sensor.
Good luck dont forget to rate.