will an imperfect engine coolant temperature switch cause my cars idle to surge during the first few minutes of driving? start up in cold weather my car jumps from 2300 - 3000 rpm till it warms up and goes down, the colder it is the higher it goes. then after a few mins the idle surges anywhere from 1000rpm - 2500rpm, this stops after a while and the car runs fine. i think im getting a connection, just not a very strong one. anyway your help is appreicated. thanks.

 

Try your FITV.

 

as well as the IACV... if anything SiR-G DC should know

 

i took off my fitv and cleaned it tightened it and now my cold idle isnt reaching 3 grand which is good, but i cant shakje the fluctuating idle. next is iacv then back to the ect, any other ideas?