2008 Power Stoke Engine RPM

[Rambler]

I have a 2008 and I've noticed the engine seems to run a high RPM when warming up in the Winter. It also seems like there is times when the Engine will start running a high RPM when I have it in Park after it has warmed up. Example is I'm sitting at a drive up window and all of a sudden the RPM starts up and the only way it will come down is to step on the brake. Does any of this sound weird or is it normal. I have around 25,000 on the truck.

 

[Bighurt]

It's programmed into the PCM, there is also a High idle up-fitter switch mod for those running a PTO.

By running the engine at higher idle it prevents wet stacking, as it burns cleaner at higher rpm. Unfortunately this only increases the regen cycle.

 

[jnbhobe]

Its actually normal, It will normally happen when the engine is cold or let it idle for a long time