A bunch of hot air

[PontiAddict]

Interesting occurrence today while in the truck. Had the defroster on because it was raining out...

Turned off the defroster and let the climate control go back to auto, set at 70 degrees. Nice and cold on the driver's side...but on the passenger side, the vents were emitting a BLISTERING amount of heat. Ended up just closing the passenger vents. About 10 miles down the road, the vents were reopened, only to find nice cold air coming out again.

I did a search and found that 04 MY GM trucks with auto climate control seem to have this problem, more than other years. This is about the second time its done this, the first time being memorable, but less obvious an issue. I didn't see any solutions posted with the other problems I found, so I figured I'd ask the best GM truck club I know of.

Anyone have any insight?

[GaryL]

Sounds like the temp control door for the passenger side is starting to stick. The passenger side is the one that is toughest to get to. It is in the center of the dash high up, so the dash has to be removed to get at it.

[PontiAddict]

Oh joy. Yeah...sometimes I'm thankful I don't have all the amenities in my Bonneville. Sometimes I wish I had an SSEi and then I see people go through things like their auto climate starts going wonky...just didn't know these trucks had that issue! I guess when you're driving a fully loaded vehicle, like my truck, something, by odds, is bound to go wrong...of course its going to be something mechanical! Hah, hope its good for a while..don't really want to, nor have the time to tear into that anytime soon.

Thanks for the information though.

Anyone with more specific cleaning/replacing/maintenance suggestion towards it is welcome to share.:great:

[collinsperformance]

i say heat/air blend motor as well.....mike

[retired2001]

I feel your paiin! My '04 Z71 is having similar problems. The hot air comes out all of the vents and I have to turn to the "defrost" positiion to get it out of my face. After awhile I can turn the AC back on and it works alright. Intermittent problems are terrible to trouble shoot.

[collinsperformance]

intermitant maybe connection or motor on the way out. why not get one from the junk yard or a couple spares and swap it out and see if the issue goes away? dirt, hair, or other stuff can jam up the motor and cause the motr to work or not work and too much spilled coffee or soda can gum it up and the heat melts the goo and works fine. i swap it out and see if the issue goes away. is so leave the new part in or go spend more money and get a new motor from the dealer....mike

[Tunnelmotor99]

I have the manual dual zone system and when I bought the truck (05 Silverado) 1 month ago there was an irritating popping/clicking noise coming from the evaporator case. I found a bulletin about this using GM SI and they call for reprogramming the HVAC control module. I reprogrammed it and also reset the actuators and voila! the popping is gone!! Apparently the actuators can get "lost" and revert to a default mode. Don't know if reprogramming will fix your issue but its just an idea.

[PontiAddict]

That's very interesting. I definitely will ask the dealer about that.