07 KJ P0507 code

[StageHand]

My 07 KJ Sport 4x4 w/ 170.5k keeps throwing a P0507(idle higher than ...)code. This happened a while...3 months or so ago. I kept getting it checked at a-zone and it was always the same code. I noticed the fuel mileage dropped...345 mi/tank to 315 mi/tank.
I have replaced the throttle body, Serp belt, plugs, oil/filter, all within the last 300-ish miles. The code keeps coming back. If the idle is higher it is not by much...but enough to trigger the code.
I just bought a code code reader and it shows the same P0507...I can just clear it myself now. It seems to happen about every 5 - 8 days. I will run a trip diagnostic tomorrow and see if it shows any emissions codes.
In the meantime...any thoughts?
Thanks in advance.

 

[StageHand]

So I left the Innova 3040c hooked up during the drive to work today (30 mi).
Although no codes were thrown the display says that O2 sensors and Evap are not right....getting a yellow light on emission monitor and those icons are blinking on the display.
Is it usually the Evap purge solenoid/valve that goes out or wears?
Could the high idle code and reduced fuel mileage be related to these?
Where is that on an 07 KJ?
FSM links always seem to skip 07 KJs. I know ..... I will pick up a Chiltons or Haynes as soon as I can.
Thanks

 

[Sandye]

Having the same issue with my 07. It seems to be a common issue with Jeeps

 

[tommudd]

. It seems to be a common issue with Jeeps

no

 

[Ksat]

You may have a vacuum leak causing high idle and increased fuel consumption. Is your scanner able to read the live data? Problem might also be related to the IAC valve.