Mercedes GLS exhaust flap issue

Louder exhaust noise, eh? Sounds familiar! Had a similar issue with my old Audi A6. Is it a constant drone, or does it change with RPMs? Could be the flap actuator acting up. Those things are notorious for failing. Did you check the wiring to the flap motor? Sometimes it's just a loose connection. Exhaust valves are unlikely to be the cause. Before you go replacing the whole exhaust system, take a peek at the flap motor and its connections. Is the flap stuck open or closed? Knowing that could save you a lot of time and money. What kind of error code are you getting?

Thanks for the quick reply! I will check the wiring. To answer your question, the noise seems to be there all the time, but it gets a bit louder when I accelerate. I haven't checked the error code yet, but I will do that now. If it is the flap actuator, is it something I can replace myself, or am I better off taking it to a mechanic?

Alright, constant noise that gets louder with acceleration points even more to those exhaust flaps being stuck open, or the flap actuator not doing its job. Honestly, swapping the flap actuator could be a DIY job, but it can be fiddly. Do you have the right tools and a bit of experience? Plus, you might need to clear the error code afterwards. If you're not comfortable with that, a workshop is probably the safer bet. They can diagnose it properly and make sure everything's working as it should. Better to be safe than sorry, right?

Okay, thanks for the advice! I took it to the workshop, and you were right – it was the exhaust flap. They replaced it, and the error is gone, also the exhaust noise. The final repair cost was 190€. Appreciate your help!