knocking sound
Thread Starter
Heel & Toe
Joined: Nov 2011
Posts: 20
Likes: 0
From: Houston Texas
knocking sound
Have a 13GS with under 1K miles and notice with the AC on I hear a knocking sound coming from what appears to be the console area by the shifter. Anybody else seen this?
Pro
Joined: Aug 2003
Posts: 620
Likes: 45
From: Raleigh NC
Mine does it too.
I've been searching the forums for HVAC noises, but haven't found what I've been hearing.
I even recorded it on my phone, and I uploaded to YouTube, but have been unable to find the link to my video.
If I shut off the HVAC, it goes away.
To me it sounds like it might be an actuator of some sort that is trying to open and close a vent or something.
Mine's a '13 GS, too.
Noticed it the first week I had it.
It's very noticeable.
Thread Starter
Heel & Toe
Joined: Nov 2011
Posts: 20
Likes: 0
From: Houston Texas
Sounds like this...
http://www.youtube.com/watch?v=oBM8e4qdSM8
http://www.youtube.com/watch?v=oBM8e4qdSM8
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Melting Slicks
Joined: Dec 2006
Posts: 2,694
Likes: 106
. Having to do that to a brand new car is almost an insult. Good luck OP. And please keep us posted.
Drifting
Joined: Feb 2012
Posts: 1,796
Likes: 37
From: skiatook oklahoma
no matter, i'd get it into a dealership, so its logged as possible later or actual now, warrenty work.
Melting Slicks
Joined: Feb 2007
Posts: 3,488
Likes: 0
Hmmm, I had a related issue which was a high pitched whine when running the A/C or heater which got worse with the fan speed. It was obviously the fan motor. I chose to live with it fearing a disassembly of the dash.
I suspect the knocking sound is similar to the whine in that it has something to do with the fan assembly or the motor itself. I would guess the fan rotar piece needs to be repositoned as it is touching the vent wall or fan guard.
Good luck...
I suspect the knocking sound is similar to the whine in that it has something to do with the fan assembly or the motor itself. I would guess the fan rotar piece needs to be repositoned as it is touching the vent wall or fan guard.
Good luck...
Pro
Joined: Aug 2003
Posts: 620
Likes: 45
From: Raleigh NC
On mine, the knock doesn't get faster.
It seems like it starts when the HVAC is trying to change settings (dash vents to floor vents, etc).
It doesn't change with fan speed, but it stops when I shut off the HVAC.
On a possibly related note, I will get airflow from over the top of the dash when it's set to floor.
I noticed cold air was blowing in my face when the HVAC was set to a temp that should have been causing warm air to come from the floor.
I can make that stop by switching to the dash vent setting.
I really hate for them to have to rip my whole dash apart.
It seems like it starts when the HVAC is trying to change settings (dash vents to floor vents, etc).
It doesn't change with fan speed, but it stops when I shut off the HVAC.
On a possibly related note, I will get airflow from over the top of the dash when it's set to floor.
I noticed cold air was blowing in my face when the HVAC was set to a temp that should have been causing warm air to come from the floor.
I can make that stop by switching to the dash vent setting.
I really hate for them to have to rip my whole dash apart.
Thread Starter
Heel & Toe
Joined: Nov 2011
Posts: 20
Likes: 0
From: Houston Texas
On mine, the knock doesn't get faster.
It seems like it starts when the HVAC is trying to change settings (dash vents to floor vents, etc).
It doesn't change with fan speed, but it stops when I shut off the HVAC.
On a possibly related note, I will get airflow from over the top of the dash when it's set to floor.
I noticed cold air was blowing in my face when the HVAC was set to a temp that should have been causing warm air to come from the floor.
I can make that stop by switching to the dash vent setting.
I really hate for them to have to rip my whole dash apart.
It seems like it starts when the HVAC is trying to change settings (dash vents to floor vents, etc).
It doesn't change with fan speed, but it stops when I shut off the HVAC.
On a possibly related note, I will get airflow from over the top of the dash when it's set to floor.
I noticed cold air was blowing in my face when the HVAC was set to a temp that should have been causing warm air to come from the floor.
I can make that stop by switching to the dash vent setting.
I really hate for them to have to rip my whole dash apart.
Pro
Joined: Aug 2003
Posts: 620
Likes: 45
From: Raleigh NC
Anyone else seen this problem yet?
Seems odd two different '13's are experiencing the same thing.
I think there would be at least a few more.
The knocking sound is annoying, but so is the inconsistent HVAC operation.
One time I had the airflow set to dash vents, and nothing came out of them, even with the fan all the way up.
All of it was coming out of the defrost vents.
I had to shut the HVAC system off, then back on.
Also, if it's a sunny day, but cool out, the system will be in bi-mode (floor and dash vents). But it comes out of the defrost vents, not the dash vents.
I've learned to live with all of this.
I'm scheduling a service visit before the Bash, but I'm not sure I want the dealer ripping into my dash.
Maybe better to ask at one of the C6 troubleshooting sessions at the Bash.
Seems odd two different '13's are experiencing the same thing.
I think there would be at least a few more.
The knocking sound is annoying, but so is the inconsistent HVAC operation.
One time I had the airflow set to dash vents, and nothing came out of them, even with the fan all the way up.
All of it was coming out of the defrost vents.
I had to shut the HVAC system off, then back on.
Also, if it's a sunny day, but cool out, the system will be in bi-mode (floor and dash vents). But it comes out of the defrost vents, not the dash vents.
I've learned to live with all of this.
I'm scheduling a service visit before the Bash, but I'm not sure I want the dealer ripping into my dash.
Maybe better to ask at one of the C6 troubleshooting sessions at the Bash.
Melting Slicks
Joined: Oct 2010
Posts: 2,220
Likes: 16
From: Sugarhill Ga
does the noise get better or worse if you change the temp ? or if you change from floor to dash? if it does then 1 of the motors that regulates that action is loose or binding up. they are called mode door actuators.
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
My '13 definitely does not make a sound like that. The dash on these cars is pretty easy to take apart, so you might consider pulling it apart to take a look without the console and dash pad in place. It may help you to narrow things down a bit.
Pro
Joined: Aug 2003
Posts: 620
Likes: 45
From: Raleigh NC
Like it's trying to close the floor vents and open the dash ones, but the actuator, is stripped, (or binding) and it can't completely close or open a door...so it keeps trying.
When I shut off the HVAC, you can hear it immediately stop.
I guess if getting into the dash is not that big of a deal, I'll let my local dealer look at it.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
that sound is familiar. not on my vette, but on another car it was the electronic acutators/sensors. and they do move the "doors" that route the air flow.
in this other car, it looks like a sealed piece of plastic about 2.5x2.5 by about 3/4" thick. mine didn't require disassembly of the dash, but there is a third one in there that does. we would be talking intensive labor charges.
since yours are new cars, it's a 3/36 thing if that's what it is.
in this other car, it looks like a sealed piece of plastic about 2.5x2.5 by about 3/4" thick. mine didn't require disassembly of the dash, but there is a third one in there that does. we would be talking intensive labor charges.
since yours are new cars, it's a 3/36 thing if that's what it is.
Drifting
Joined: Feb 2012
Posts: 1,796
Likes: 37
From: skiatook oklahoma
i had saved this for other reasons. of NO value for ya, but it does show all the parts in that dang thing!! noise caused in here somewhere, i wouldnt want to be the one to tear into it.. lol
Pro
Joined: Aug 2003
Posts: 620
Likes: 45
From: Raleigh NC
Thanks for the info, all!
I'm scheduling an appt to have it looked at.
That's one of the reasons I traded my '06 for a new one...the warranty.
Might as well take advantage of it while it's there!
I'll post the results...
I'm scheduling an appt to have it looked at.
That's one of the reasons I traded my '06 for a new one...the warranty.
Might as well take advantage of it while it's there!
I'll post the results...