High idle at startup, how long?

[Briarsmoke]

Brand new 2022 tradesman 4x4 6.4. Upon starting the engine the idle sits at around 1100 and doesn’t want to come down. Let it idle like that a minute, go ahead and put it in drive and drive it a little, shortly therafter the idle in park is 700 where I assume it should be. Turn it off and restart it a few minutes later (90 degrees outside and engine is still at operating temperature) and it’s back to 1100. Sat there 4 full minutes idling at startup in 90 degree heat with the temp guage at operating temperature and the idle won’t drop from 1100 unless I put it in drive and drive it a bit. Thoughts?

 

[Cajones307]

My 22 does the same thing, I just hit 1200 miles and have only owned it this summer. I thought maybe the computer needed to adjust to normal operating conditions.

 

[Riccochet]

It has less to do with engine operating temperature and more to do with catalyst operation. The computer is telling the engine to pump more air and fuel through to get the catalytic converters to operating temp. It's an emissions thing.