I've been having this problem with my '06 2500HD LBZ. Every once and a while when I'm accelerating the REP message pops up at the DIC and the computer takes over the gas pedal. If I try to floor it it'll only go about 25. But if I gently push the pedal with the tip of my toe it'll eventually climb up to 55. Message disappeares and everything returns to normal if I turn off the ignition for 30 seconds. Sometimes it may be ok for weeks and then do this twice in one day. I've noticed that the problem is almost always related to heavy acceleration and I think it's more common in wet conditions but can't say for sure. Load seems to have nothing to do with the problem.

The truck is stock except for the plow installation and a speed limiter. I've plugged in my scanner but it doesn't show any codes even with the REP message still in the DIC.

Any thoughts on this one...?

Ps. I know someone will ask about the speed limiter so I might as well explain it. I live in Finland and because of some BS EU law all trucks (10/2001 and newer) with GVWR over 7700 lbs have to be equipped with a speed limiter set to 55. It really sucks, I know...