Cold start won’t high idle anymore

[MikeBMW]

4 hours ago, AR10 said:

If that does not beat all. My 2018 5.3 litre never idled high at start until a week ago after changing water pump. Now I'm confused, was it not working correct before or is it not correct now? I don't like the high idle.

It should only happen at start up and then slow down.
I'm just guessing it's a way to add some extra alternator boost to re-awaken sleeping modules?
It should slow down in less than a minute.
I'll do mine, right now, on a cold start and see how long high idle remains (caution, I do have a touring Borla exhaust installed).

 

Edited March 25, 2023 by MikeBMW

[M1ck3y]

There is no high idle on the half tons; Duramax only.

 

Rev's are slightly higher with cold starts to light off the cats.

[MikeBMW]

4 hours ago, M1ck3y said:

There is no high idle on the half tons; Duramax only.

 

Rev's are slightly higher with cold starts to light off the cats.

There is high idle on cold start, however on the half tons.
See my video above.
High idle option on running while in park, though, is reserved for the Duramax, as you stated.

Edited March 31, 2023 by MikeBMW

[sic02ss]

Bringing this up again, no one find an answer for this yet? I cant find anything on google, seems alot are having the issue but no one has a solution and the threads just stop like this one lol! I know its not a big deal but I like the way my cold start sounds and its annoying when I anticipate it and it starts quiet like ive been running the truck for hours. 

[Bob Oke]

I have a 2020 Silverado High Country 6.2, and my cold start/high idle stopped on first start up as well!! 
 

Has anyone found an answer ?