When the truck has warmed up and been driven 5-10 miles, the problem occurs. If i stop at a light or stop sign after this warm up period, there is a 2 second or so throttle delay. I can hear the rpms rise right away, as i get on the throttle, but its another second or 2 delay before the truck moves.

this only occurs after the truck has warmed up, as it runs perfect for the first few miles with stop and go's.

i also noticed, that when im stopped at a light, after the same warm up period in hot conditions, that if im stopped at a light or something, if i take my foot off of the brake and roll a couple feet, there a heavy vibration (as if i was rolling on extreme offroad tires at a low speed, like a bounce almost. Once i take off, its gone immediately though, and it doesnt occue all the time.

any ideas?