Story of why.. I was driving my slk230 in the rain today. I ran through a shallow puddle, then a noticable difference was made to the sound coming from the front through the firewall. The sound is not a noticeable difference than before when at idle, but during acceleration is when it is at it's peak. Lots of cabin noise. Sounds like maybe a broken exhaust, or maybe just a manifold gasket, but if someone thinks its anything else I would like to know. Thanks for always being here. j

 

Have you opened the hood and had a look?

Also check the reflector shield next to exh to ensure it isnt touching anything.
There is a flat panel under engine. Is it still fastened (2 clips at front, 2 screws at rear.)

Bazzle

 

Thanks for the reply, I have looked and don't see noticeable gaps or break. The heat sheild was fine and secure. I did stick my nose into the gap between the heat sheild and the manifold, my glasses fogged and it smelt like exhaust. I also checked the rear exhaust and had very little pushing onto my hand. thanks j

 

Exhaust leak may be on the cards. There is a flange joint that may be loose .

Bazzle