irenesbob

When my 2016 A6 has been parked overnight either in the cold outdoors or in the garage (temp range from 42- 50 degrees F) and I close the driver’s door there is a single not-so-loud noise (rattle, pop, whatever) that seems to be coming from the rear shelf. Once the car is underway and running (even for just a few minutes) the noise no longer happens when I close the door. I have crawled into the trunk and nothing seems loose there. The ceiling light does not seem loose either. I have Bose, which I understand has the subwoofer mounted to the rear shelf (I think I saw it). It is odd, because once the engine has been running even 5 minutes or so, I cannot replicate the sound, even if I drive all day going on various local trips and open and close that door many times. It is hard for the dealer to replicate the sound since the car is already warm once they get to it.
I got the car in early November and did not notice the sound until a month or so later as temperatures got colder. Perhaps it will be gone next spring as things warm up and I should just live with it, since it only occurs once each day. Any thoughts on this issue? Anyone have a similar issue?

irenesbob

As it is getting colder put it is taking longer for the noise to disappear.

1st Time Audi

The loaner I have has a slight rattle like something is sliding back when I accelerate faster than normal. It has only happened a couple times...

porksoda

its the trunk lock actuator, i have the same issue going to bring it up to the dealer.

only happens when i open the driver door.

irenesbob

Thanks. Do you experience the same thing that after the car warms up a bit the noise goes away even if you open and close the driver's door repeatedly?
I had thought it might be the housing around the third brake light which is tight against the rear window glass. Where is the trunk lock actuator located?

porksoda

Sorry for the late reply, I am doing more experiments with the thunk noise when i open the driver door and this is what i found so far.

- I park my car in my garage so i don't lock the car (not sure if this matters yet or not).
- I can replicate the noise by starting the car and opening the trunk and closing it, after that if i open the drivers door it gives me a thunk.
- Another thing to notice which i never really cared about was that when i go towards the car and try to unlock the trunk by pressing the button it usually takes twice for me to open it.
- Another odd noise thunk i heard was from the front of the car which i did not hear again after i heard it one day so maybe mud or ice in the wheel well.
- Most importantly i want to test it out and make sure its the trunk and not another actuator somewhere else, which i will confirm tonight.

I am documenting and experimenting this problem and will update this thread once i do more experimenting tonight with a friend.

Sounds like your issue might be a bit different than mine though, if you cannot replicate my process to get the noise. I have B&O audio and if i turn it up or have a bassy song the trunk and all the plastics rattle a lot, reason i am mentioning is that it might be a insulation issue, you mentioned third brake light - which is held in super tightly. It maybe your parcel deck which have been a problem for cars since the begging of time.

If you are able to replicate the sound perhaps get your wife to sit in the back and see if she can pinpoint where its coming from?

cheers

porksoda

Looks like i was wrong, it is not the trunk actuator - unless it is in the location described below.

I am able to replicate the thunk noise and it comes from the rear left side of the trunk near the bumper and or the rear fender area.

I am not sure what is located there but it sounds like an actuator going off in that area when i open the drivers door.

porksoda

Update:

Was at the dealer... i was unable to replicate the situation but the shop foreman explained two vents in the car and suggested that maybe causing the noise. This may explain my issue and yours. I will troubleshoot some more.

cheers

irenesbob

I think my noise was different from yours. It occurred only when the car was cold after sitting overnight in sub-50 degree weather. The noise did not occur when closing rear doors in same conditions and only occasionally when closing the passenger door in the same conditions.
I took it to the dealer Wednesday and they fixed/eliminated the noise. From the service report:

My complaint:
“Customer states a noise from rear shelf when closing driver’s door – only happens when car is cold and outside temperature is cold.”
Cause:
“Verified noise and resolved. Found reverberation type noise when the front driver door closed. Found the sunshade rattling on the headliner causing the noise.”
Action:
Remove and reinstall glass tilting roof panel. Remove dome light and visors and related including headliner retaining ring. Lower headliner and adjust shade and retaining ring so they do not make contact. Replace sunroof shade guides. Reinstall all. OK no noise, performing to specs.”

So far the noise has not happened even though it is under 20 degrees outside. The only I noticed was a very slight/low wind noise from the sunroof (barely audible with the shade closed) at an indicated 70 mph on a very windy highway. It could be just the very cold day and the high winds, but it could be they did not re-install the sunroof panel properly. I advised the service advisor today and I will monitor. In any event, the dealer did a good job of sleuthing and correcting the issue, I could have sworn it came from the rear shelf.

porksoda

irenesbob. Thank you for posting the resolution to your issue, i may try looking at the sunshade as well. Will help me with my noise perhaps... will update this thread when i have a resolution for future readers.

cheers