Mercedes GLC problems with the engine, engine indicator light keeps coming on

Hey, sounds a lot like a problem I once had with my 2012 Mercedes C-Class diesel. My symptoms were pretty similar: black smoke, check engine light on, loss of power and strong exhaust odor. In my case, one of the lambda sensors was defective. The lambda sensor measures the oxygen content in the exhaust gas and helps to regulate the fuel-air mixture. If it is defective, this can disrupt the exhaust gas aftertreatment and lead to the problems you describe. I went to the garage and the diagnosis was made relatively quickly. The defective lambda sensor had to be replaced. It wasn't a huge problem, but something that should be dealt with quickly so as not to risk any consequential damage. Hope this helps you! Greetings

(Translated from German)

Hey, thanks for your reply! It really sounds like the problem could be similar for me. Can you remember how much you paid for the repair? And has anything else happened to your car since then? Kind regards

(Translated from German)

Hey again! I'm glad that my answer has helped you. Yes, the problem with my car was actually solved by the workshop. The exhaust aftertreatment malfunction was fixed after the defective lambda sensor was replaced. The cost of the repair was €375. Since then, my car has been running perfectly again without any further problems. I hope your repair goes just as smoothly! Kind regards

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Hey, thanks for the info! 375€ sounds okay, I would have expected more. I'll probably go to the garage and have the lambda sensor checked. Keep your fingers crossed that this is the solution. I'll let you know again when I know more. Best regards

(Translated from German)

Good day, it sounds like an exhaust aftertreatment issue, it could possibly be the DPF or EGR. I would recommend that you get it checked by a trusted mechanic for a full diagnostic check. I personally have had similar issues in the past; replacing the DPF fixed it. Good luck!