Car overheating while engine is off

[Amf3ar]

The dashpot retracts too fast.. About in 4-5 seconds.
After that, rpm stay on 1100-1200.
If I press gas pedal (just an hit) they go to to 750-800.
I tried another dashpot with no luck.
Can be a TPS problem too? Cause a mechanic removed it too clean the TB... dunno if he put it on again in the right position...