2009 Chevy Impala

Since Tuesday, whenever I open my door or start the car (remote start) when the car is cold, there is a loud clicking/knocking coming from inside the dashboard. It doesn't influence how the car drives. It stops on its own after about a minute. During this clicking, the vents will not transition from the Forward to Windshield...or move at all. The fan speed appears to be stuck too, as I can only get up to half of the max air speed. After about a minute, it stops on its own and everything is back to normal; vent transition, air speed, etc.

The whirring is independent of whether or not the car engine is on; it appears to only be related if the battery is accessed (or otherwise if I open the door, not sure if unlocking does this too). If I shut down the car when this is going on, it keeps clicking and will eventually stop. It blows out cold air, not sure if this is A/C cold though. After the car has been driven around and warmed up a little bit the whirring will not come back.

I had thought it was related to the battery, which had a ton of corrosion on it, but after removing and cleaning the leads, when I reconnected them to the battery the clicking began immediately again.

Here's a video - I tried to rotate it using youtube but that isn't working for some reason.



I've found a possible similar problem/solution here, looks like a fairly simple fix. http://www.cadillacforums.com/forums/cadillac-forum/t-228556.html

Quote :

"If it's a rhythmic ticking noise that lasts 10-15 seconds coming from behind the radio when the car is first started you may have a bad mode door actuator. Are you able to manually change where the air comes out.... dash.... defrost... floor with the "mode" switch on the HVAC panel? Bad mode door actuators rarely set a DTC.... the actuator still moves... but a stripped plastic gear keeps it from moving the mode doors."

However I can't find any known issue similar with an Impala.

Any ideas? It seems I could fix this on my own but I don't know how to confirm that this is the problem. The nearest dealership is 30 minutes away, not sure if my warranty is still good, I'm doubtful about the local car shop, and I'd rather have some knowledge before I go anywhere anyway

More possible fixes:
http://www.justanswer.com/chevy/4um91-chevrolet-impala-ls-blend-door-actuator.html
http://chevroletforum.com/forum/uplander-31/blend-door-actuator-20542/

Looks like I need to see if it will blow out hot air too

[Edited on June 30, 2011 at 4:00 PM. Reason : lkj]

6/30/2011 3:56:29 PM

yeah... something is hitting the fan, you need to take it a part to find out what.

it could be anything from the blend door to a mouse either way the quicker you fix it the better.

6/30/2011 5:25:48 PM

I'm more confused by why it automatically starts doing it when you unlock the door and before you even start the car. Unless the climate control resets to a default position on unlocking it I'd think it was a really shitty relay that kept popping, although it does sound closest to a stripped gear. Had anything recently sitting on your dash that may have fallen into the defrost vents?

6/30/2011 9:06:59 PM

slightly related

my mom had this ragged taurus when we were kids that she hauled our asses around in. one of us left one of those stickers they used to hand out at the bank drive-thru on the dash (still on the wax paper backing stuff) and it got down in the defroster vents. stayed there for years until she got rid of the car. looking back it was probably annoying as fuck to her.

6/30/2011 10:01:31 PM

To me this looks like a video thread to me.

6/30/2011 11:43:46 PM

Hvac actuator. Just developed the same problem in my z06. Fucking extremely fast GM garbage.

7/1/2011 12:08:37 AM

I found the source setting of the problem

The air conditioning temperature switch (ranges ble to red).

The clicking happens if the driver's switch is fully blue. Nothing else matters, if it is set to blue and the fan is on then it clicks. Completely irrelevant if it is set to forward, windshield, full blast, teeny bit on, a/c on or off, only cause is the full blue setting. Passenger's side doesn't matter either.

Turning it about 4 notches from fully blue stops the clicking. I took another video but can't upload it right now.

So some weird electrical contact failure?

[Edited on July 1, 2011 at 4:31 PM. Reason : dfh]

7/1/2011 4:28:45 PM

no, that blue/red selector thing sets the blend door position. your problem is probably with that door.

7/1/2011 5:46:26 PM

^Makes sense, electrical contact was suggested by a coworker. Guess I'll have to dig around in there today.

Although, it does seem like it has stopped after driving around with the vent on ~80%, and I didn't hear the clicking when I put it to full blue. I'll still have to double check I suppose.

Here's the video.

7/2/2011 11:11:48 AM

Double post, but seems like NRR and others were right. Here's a forum where they have the exact issue...for some reason I never came across it in Google searches.

http://www.impalaforums.com/mechanical-and-electrical-problems/255177-2008-impala-passenger-dash-clicking.html

Thanks for the help!

7/2/2011 12:46:43 PM

it's a bitch to get to on some cars. good luck.

7/2/2011 12:58:23 PM

I ended up taking it to the dealership a few weeks ago, they couldn't replicate the problem and sent me on my way. It stopped for the most part, but then started up again maybe two weeks ago a little, then did it a lot this week. Last night I got home, turned off the car, and on my way to the door I heard it start clicking again. Said fuck it and went inside.

This morning, the fucking battery was dead. Jumped it with my girlfriend's car and went to work, was about to go to the dealership but the battery was dead again (an hour later). Couldn't get it to jump at all with a coworker's truck, so I pulled the battery out (why the fuck is it so hard to do that btw). Managed to get battery acid all over the place. Now I gotta go get a new battery and then take the car to the dealership. Could probably had gotten it towed, but the dealership is 30 minutes away and they'd probably be all "lol your battery sux, here's your $500 bill for nothing" and the problem wouldn't be fixed

Fucking piece of shit.

8/30/2011 11:11:51 AM

i watched the video again and i think i spotted the problem right there in the middle of the steering wheel

8/30/2011 4:19:09 PM

Yeah, you're probably right

8/30/2011 8:03:42 PM

First video would be a good candidate for a continuous loop at Guantanamo

8/30/2011 11:37:35 PM