I have an 07 ss, and I noticed that my car is making a knockin noise when the car is OFF! It usualy last for about a minute, then it stops... I 1st noticed it when I was walking away and hit the button on the remote to lock the car. Then I would hear a contstant knocking like maybe a vent or lever is trying to open. The noise is coming from the passenger side, but I can't tell if its inside the car or under the hood. I'm dreading bringing it to the dealership, because they take too long! All I can say is HELP! Thanx in advance!

 

I've been getting the same thing, anytime I lock or unlock the doors. Or if they're not locked then it starts when I open up the door.

I've heard people say it has something to do with the A/C in the past but it seems to be coming from inside the firewall on the passenger side for me. It used to only do it when I used the A/C but over the last couple months it's been everytime, A/C, heat, or nothing.

Anyone else have any ideas? I've looked but can't figure it out. One of my roommates is an electrical engineer major and thinks it's electrical but can't find it (imagine that)

 

Sounds like we have the same problem! I checked the glove box, the side panel on the passenger side between the door and dash, and even under the hood,later on I'm going to upload some vid or photos

 

He man, I got a call from the dealer this morning (took my car in due to overheating issues) and they said it's the heater core return actuator. Said it's a $2-300 fix.

 

Got my actuator replaced for 200$ been one month and the noise is back. UNBELIEVABLE!