1300-2000 rpm warm idle in park or neutral

[Shaman]

Just started today. 2 shorter drives and one longer two way drive(45-60 min) yesterday. Used the remote start this morning. Idling fine when I got out to the car 3 minutes later. Drove the 15 minutes to work, get to my parking place, park, and put it in P. Idle is going up and down evenly between 1300-2000. This afternoon I ran an errand, and it is staying near 2000 longer than 1300. Tried revving, no change. Throttle cable not moving when I checked this morning. May be tight, but definitely not moving.

IAC valve was replaced about 6 months ago. Vacuum stays around -8 psi(not inHg) through the fluctuation.

 

[Trav]

Quote:
Idle is going up and down evenly between 1300-2000

Fluctuating idle can also be caused by a faulty TPS.
You can usually test them with a digital multi meter, check the service manual for specs and procedure.

 

[Klutch9]

What about a vacuum leak? Does your car use a MAF sensor or a MAP sensor?

 

[demarpaint]

In addition to the TPS, I'd check for vacuum leaks, and the IAC as well.

 

[Shaman]

Map sensor. After the drive home yesterday, it went away. No problem today. If it comes back I will look into it some more.