Black exhaust smoke and loss of power in Skoda Octavia 2012: Possible causes?

Hey, I had a similar situation with my Skoda Superb, model 2015, where the engine control unit was found to be defective. It was quite a problem because it is responsible for fuel injection, ignition timing and other important functions. The symptom was exactly like yours: reduced engine power, rough driving and lots of exhaust fumes. I don't know if it's the same for you, but a defective control unit could be a cause. It is certainly better not to replace parts on suspicion, but to carry out a proper troubleshooting. So, take it to the workshop and have it checked. But don't worry, with a proper repair your car will hopefully run like new again. Good luck, old man!

(Translated from German)

Hey, thanks for the quick reply. I actually didn't have the engine control unit as a defect on my screen. Do you have any idea what you paid for the repair? And did you have similar problems afterwards or has your Superb been running smoothly again since then? Greetings!

(Translated from German)

Hey, no problem, that's what we're all here for, right? So, the repair cost me a bit - exactly 1000 bolts, to be precise. But afterwards the Superb ran like clockwork again, not the slightest trace of smoke from the exhaust or reduced performance. At the next workshop visit, the lambda sensor heater was checked again and was completely in order. Since then, the car has been running smoothly! So, cheer up, it'll be fine! Best regards!

(Translated from German)

Thanks dude, that's just the info I needed! Your experience gives me a bit of hope. I will then go to the mechanic and have it checked in that direction. It all sounds expensive, but the main thing is to get my Skoda back on its feet. Thanks again and best regards!

(Translated from German)