What causes HIGH idle in gear?!!?!
 

My car has been acting wierd as of late. The car seems perfectly okay in idle and once i put it in gear, it goes up to about 2,000rpms and stays there. While cruising, i dont even have to give it gas, becuase it stays at around 2,000rpms and actually pushes my car as though i would have the peddle down slightly. I didnt even touch the gas peddle and slowly it would go from 10mph to 15mph to 20mph and keep on going. When i come to a complete stop, I have to hold the brake down hard becuase it feels like it wants to still go. If i hold the brake long enough, it hesitates and slowly goes back down to a good idle, but if i let go of the brake, it goes back to what it was originally doing. What the hell would cause this!??!! and no codes are being thrown either

Its the tune, it needs to be adjusted. ODBII PCM's like to fuck with settings after so many miles of driving, its common.

The iac valve could be sticking too, which would do this.