P20F8 on 2024 Silverado 1500 LZO 32000 miles

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"The intake manifold air control actuator (IMAC) on engine bank 1 has a circuit performance issue."

So I am on vacation, towing a 7000-pound camper, 1000 miles from home, with a lot of fishing to do for the next week before heading back. This is the one code coming up. I cleared it and it stayed off while running. When I start the truck after clearing, the check engine light stays off until I put it in drive and start going.

The interwebs seems to think it's important to address but not super super urgent.

The closest dealer is 50 miles away, and even assuming I can get a service appointment it could take days to get parts depending on the parts. I'm a little concerned that if I bring it in there and then refuse the repair on the basis of wait time I'll be in a bad spot for warranty position. Though I suppose Chevy already knows that the code lit up, since I see it on the Chevy app. Plus their surveillance system knows where I am and how far I've gone and how the truck has performed since it came up.

I don't think I notice any performance issue -- primarily they say emissions and low fuel economy, though towing through wind and mountains certainly burns both diesel and DEF. I'll get a different perspective running without the trailer today.

What I want to do is drive around (not towing) and find fishing spots for the next week, then pull the camper 1000 miles home and then take it in for service.

Just how stupid a plan is that?

Is it weird to have this code at 32000 miles?

Could low-quality diesel be the culprit? I did buy some diesel at almost-too-good-to-be-true prices the day before it lit up. But I guess I don't know beyond pricing how to evaluate diesel fuel quality.
 
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Update: closest dealer is booked up for two weeks and couldn't get me in anyway.
 
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And this morning added codes P200A and P295 A. All related it seems.
 
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Hello fellow 3max'er.


Had a conversation with Google and it's of the opinion it's not a good idea to drive it especially under load as it could cause even more damage that they might not cover. It could just be a broken wire somewhere (been there with mine for the cooling fan). Call GM roadside assistance since you are still under warranty and should be able to help on this emergency situation.
 
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I'm getting a new intake manifold. I drove to a dealer 120 miles away who could get me in on Tuesday. I planned to leave it there and rent a truck but they said I was good to drive back, drive around fishing, and tow the 7000 pound trailer over Teton pass. 80% chance I wouldn't go into reduced power mode. Not sure where they pulled that number out of.

Good thing I went today, they have to order in the part, if I hadn't showed up until next Tuesday I'd have had to wait on parts. The diagnostic took all of five minutes, they just hooked up their scanner and it said new intake manifold and that was that.
 
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Whenever "In Doubt"...

WTF.jpg

Go "The Cautious Route"...
 
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I'm getting a new intake manifold. I drove to a dealer 120 miles away who could get me in on Tuesday. I planned to leave it there and rent a truck but they said I was good to drive back, drive around fishing, and tow the 7000 pound trailer over Teton pass. 80% chance I wouldn't go into reduced power mode. Not sure where they pulled that number out of.

Good thing I went today, they have to order in the part, if I hadn't showed up until next Tuesday I'd have had to wait on parts. The diagnostic took all of five minutes, they just hooked up their scanner and it said new intake manifold and that was that.
I can guarantee you that the scanner did not say, "new intake manifold". A related TSB, for the multiple codes will, though. Hope it all works out for you.
 

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