I had one with some weird symptoms includeing doing that ocassionally, turned out to be a bad knock sensor. Looking back it would be real easy to diagnose but it took me a while, then I unplugged the knock sensor and the truck ran like new, plugged it back in and same thing. Put a new one in and it was all good and no CEL. It was not even showing anything weird on the scanner while watching the knock graphing the knock sensor but it cured it. No knock sensor code either, just some random misfires.