Please Help Identify HVAC Noise

I'm trying to pinpoint this while I've got my dash apart. Just about a minute after I turn off the truck (and sometimes when I start it) I get this noise:

https://youtube.com/shorts/FyaFmZV8LS8

I feel like it's one of the vent doors itself rubbing, but please let me know if you have an idea. Does anyone know what doors it would be operating after the truck shuts down?

 

I have the same issue, though mine is nowhere *NEAR* as loud as that. LOL

 

Thats the basement door. Where the boiler is. It’s scary down there.

 

Alright, I’ll just live with it then. haha

@Kung might have to do with the fact that that mine is approaching 300k km’s.

 

In my professional amateur opinion it is 100% a noise, and 20% maybe not

 

Blend door?

 

Mine has been making a similar noise since i got the truck, doesn't really bother me, I assumed it was normal. Lets me know my blend door is working too. I'm sure a little silicon grease would make it nice and quiet.

 

IMO a blend door for the AC/heat. I'd be worried about the motor burning out.

 

Yes, that is the blend door resetting position. It automatically does that after you turn off the truck. Not sure if the noise is the actuator or the door itself, but it's a bugger to replace. The majority of the dash needs to come off.
If you can live with the noise and it still works, I would leave it.

 

^ This

Mine made noises for a while until it didn't. Then I only had defrost, no upper or lower air. Not a cheap or easy repair.

 

Sounds like you need to shop vac the farts out of the seat cushions.

 

All the way down to the firewall....very little left.

 

Yes, it’s full open surgery.

I had it done under warranty because blend door failed at 5k. Was painful to have done on a new truck.

 

My truck wasn't that far but close. It was two days at the dealer. Fortunately the tech did a great job and added extra felt tape when he put it back together. No squeaks.

 

And I thought removing the radio surround was bad.

 

And this was at 8 or 9 PM (techs had left for the day) and we were supposed to leave for a long trip the following afternoon. We actually did leave on time.

 

Awesome response! Thanks guys, @mountainpete @MyActualName @Sundog & @Sumo91 notably. As I mentioned, my dash is apart already, so now's the time to address it. It's currently stripped down beyond what it was when I took this picture.

I like the thought of adding more felt tape too. Thanks for that.

Another question for you guys: There's one bolt to the dash "subframe" that looks like it'll hit the driver's door before coming out. How do you manage to remove it without removing the door?

 

Man...if I had my dash apart to this level I'd line the @#$# out of everything with NVH before putting it back together.

 

@thered Right now is the perfect time to check the AC drain, at the floor and at the HVAC that is being installed. There have been a couple of instances, me included, where the gasket material is partially occluding the opening. Is just something to check.

 

AND....run 1 or 2 wires all the way across from 1 door opening to the other (with extra on the ends to be able to go into the doors at a later date). I so wish I had the foresight to have done this.....

Would make wiring up power folding mirrors (in the future) easier.

I also agree with getting something like dynomat down under the carpet. Hell, your at the firewall already, why not.

 

@Sundog I don’t quite follow, what do you mean by HVAC being installed? I suppose as I progress I’ll see where this drain is and check it though. Thanks.

I plan on doing sound deadening mat, though it’s not really in the budget for this. It’s a good point though. I’ll see about it. Dynomat especially isn’t cheap.

As for running wiring, again a good idea. I do have heated, folding mirrors already. I’m sure there are other things it would be useful for though.

 

Ah...that's right. Yours is just making a sound. My HVAC box had to be replaced (twice) - blend door shaft failure (snapped) and then new HVAC box had a hole in it, leaked water out.

 

Definitely sounds like the blend door rubbing or binding on the wall of the HVAC box.

This is the inside of a 2015 HVAC box.
Here the door is in the middle, partial AC, partial heat.


Here it is closed to one side for heat only. You can see the heater core in the back of the box.


The AC evaporator coil would be at the bottom but it is removed in these photos.

Air going through the evaporator coil is cold, going through the heater core is hot. Blend door decides how much of which comes out your vents.

 

Dumb question - do they replace for just making noise?

Asking because I've had this noise as well (though nowhere NEAR as bad) in addition to the AC amplifier/solenoid thing (where you turn it on, it's blank for 30 seconds, then defaults *ONLY* to defroster mode) occasionally.

 

Thanks so much! I'll remove it today or tomorrow and get a good look.

@Kung I doubt it, though I feel like the noise is symptomatic of what would eventually burn the motor out, then need replacement.

 

Right...about 3 miles after warranty goes out. LOL

 

Any updates on fixing this?

I get a strong click/pop from inside dash on start and shout down. Now only have defrost air working. I wan to have parts ordered before I tear dash apart