So it is getting to that temperature where it would be nice to be able to set my idle to 1400-1500. But I forgot how to do this. Not sure if it is turned on in the ECM or not. And the scanner I have I'm not sure if it can read that stuff or not.

 

I think that you have to start the truck and then while in park do the following:

1) Press cruise Control - to turn on

2) Press the SET button

3) Use the Accel/Decel buttons to adjust the idle.

(Note: do not hit the brake or accelerator pedals)

I think the adjustment range is 1000-1500 RPM....

That's how you enable Manual High Idle mode, which has to be enabled from the dealer or a performance programmer....

There should also be an Automatic High idle mode that runs off the IAT and Coolant Temps....

It's also recommended not to exceed 1200 RPM on a COLD Start-Up to prevent damage to internals.