Calgarian

Just got my C350 coupe back from the German Car Specialist in Calgary and they ended up dropping the roof liner and removing and reinstalling all sunroof rack bolts. $620 including tax (5%)
The popping/cracking sound is gone for now.

ezshift5

Sunroof makes a "creaking" sound when backing from garage into the street. Sound is temperature dependent.
I'm not a sunroof fan (car was CPO - and a DEAL!!) I can't recall ever opening it........... My wife neither.

We both think it's a beautiful little coupe (It's her car). I like the fact - over almost 7 years - only one issue.
One of our neighbors remarked the other day "it looks brand new".............
Odometer reads 39k plus a little change.

ez

Topdog23

Had this problem and it progressively got a little worse over time. Quite irritating really but luckily its a really easy fix.

Open sun roof and with warm soapy water clean:

1) All edges of glass, remove any algae from under edges of glass
2) Wipe down areas where the glass meets the roof, again remove any algae
3) Wipe down all rubber seals that meet the glass
4) allow all to dry
5) Spay SILICONE LUBRICATING SPRAY onto a dry cloth and wipe all the rubber seals using a liberal amount of spray - really work it into the seals and ensure you do this all the way around

This resolves the issue completely,

I suggest whilst doing this and you have the SILICONE LUBRICATING SPRAY at hand, that you do the same with all door seals. This improves the seals and quietens the car interior and should lengthen the life of the seals..

Calgarian

Its likely the bolts holding the pano roof in place. The headliner needs to be dropped and all pan frame bolts removed and reinstalled with lock tight. Mine would do the same thing and after doing the above the roof is 100% creak free

WestonMerc

I had that fix done under warranty a few years ago. It used to make that popping/cracking sound under certain conditions. That's in the past, but still have creaking depending on road surface and weather. Im not sure if its really the pano, or plastics in the headliner. I'll have to try that silicone spray idea from topdog. Would "dry" silicone be the better option? https://www.eio.com/blogs/news/3m-si...-dry-lubricant

ezshift5

"Creaking pano syndrome" - limited to backing out of garage amid weather factors - this little CPO coupe easily wins the "best looking car I've ever acquired"...................... Fuel efficient also - IIRC 35 mpg on 900 mile round trip to Phoenix.

In nearly 10 pleasant years I've never been marooned, stranded or embarrassed - - - not so my wife (ESL related)

ez