I'm trying to diagnose a problem with truck and can't pin point the problem. If I put the truck in drive and let off the brake it will slowly climb to 40mph. I checked the tension on the throttle cable and also looked for vacuum leaks and everything seems to be good. There is a delay in the motor going to it's idle rpm(around 800). When I shift from drive to park the rpms jump up to 1300 or so for a about 3 to 4 seconds then finally drops down to its 800rpm idle. This problem is affecting my braking as well due to the motor still wanting to push forward when I'm trying to brake. I was told by a fella I work with to pull off the sensor on the throttle body and clean it so I guess I'll give that a shot along with any other ideas y'all may have.

 

Are there any codes set ? Is the check engine light on while it's running ?

 

it could be a sticky ideal air control ,or a bad TSP.