My 05 c2 Carrera (17k miles) has developed a noise coming from the right front. It's kind of a clunk/thump noise and mostly happens when turning left running over rough pavement/manhole cover etc. Although it will also (rarely) make the noise when driving forward and hitting a cavity in the road surface just so.
I just had the strut bump stops replaced which were torn and I would think the Tech would have discovered any other problems during the install.

I have removed everything from the Frunk including plastic covers, and also the glove box contents.
I'll be lifting the car to look for loose bolts and ancillary parts that could be causing the noise. Also will check subframe bolts. I'd think with only 17k on the clock it's early for this type of thing.
I should note that on smooth roads and curves there is no noise at all.
Also, the noise happens randomly but I always hear it at least once when I drive it.
Any suggestions appreciated!

 

Did you check the sway bar end links?

 

Unfortunately there are a number of things on that age car that can be on the list.....including upper strut mounts.

 

...or he forgot to button something back up. i suggest you take it back, ask him to diagnose.

 

Check the A/C line if its touching anything.
These are the silver A/C pipes next to the battery (front compartement, right side) but also the pipe and its clip located in front right wheel area (strut area).
Open front compartment/trunk and right side door too. Then close the right side door and check if the noise is noticable... if you hear it, its the A/C pipe vibrating.

I've had a noise coming from the glove box/windshield area and thought its within the dashboard. We dismantled everything and all was ok (at some cars, the source was a loose ventilation duct). We then realised the tapping/clunk noise comes from the A/C line touching other parts. The noise traveled through the dashboard and was noticable while driving... but only slow driving and on rougher pavements.
We then isolated the A/C pipes, secured the clip in the right wheel area and the noise was gone.

While you are doing is, spray some silicon spray under the entire rubber lip (from the outside) of the front windshield, maybe on the rear glass too. The windshield can also produce a sound, when slight tensions let move the glass.

I searched all over the internet and if its not a suspension/strut thing, most likely either windshield, looes vent/dashboard or the A/C line. Over time, looks like many 997.1 develop one of these issues and its always hard to trace their source.

 

Thanks Guys, some good tips!

 

Broken front spring? I know its only 17k miles but its the age. (Mine is an 05 model and one front spring went last year at 30k miles which was a good excuse to fit Eibachs ) The springs break at the base and not that easily visible and still work so not obvious initially.

 

This is going to sound stupid but after weeks of dealing with a thunk in my car I took it to the dealer. After they had it apart for 3 days they realized it was a diet coke bottle underneath the passenger seat. There is no carpet under there and upon acceleration and stopping I would get the thunk.
It's free to check.

 

Been thru the car and nothing found. Wish it was that easy!

 

Check for bad tie rods (just did inners and outers on a 997.1), sway bar end-links, strut top mounts (although you can't really check them) or the lower CA

 

Found the problem! The bolt holding the lower control arm(wishbone) to the cross member was loose. Replaced with new nut & bolt. When roads are clear I'll take it for a test ride. Hopefully I will hear nothing but that nice flat six. Thanks all!