Seeking Advice on Exhaust Aftertreatment Issues and Black Smoke in 2006 Volvo C70

Hey there, I get where you're coming from. Got a 2004 Volvo S60 myself, faced something similar a couple years back. I'm no mechanic, just a guy who knows a bit about cars from having to fix my own issues over time. Took my ride to my local mechanic. Turned out one of the lambda sensors was on the fritz. The guy at the workshop replaced it and it ran me about 375 Euro. Worked like a charm after that. Before we dive deeper into this though, could you tell me a bit more about your vehicle? Things like mileage, model, any previous issues? Might help in giving a more accurate response. Cheers!

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Hey, thanks for the quick response. Just to fill you in, my C70 has around 18,540 kilometers on it. As for previous issues, she's been pretty much problem-free, aside from the usual minor stuff you'd expect in a car this age. Get her serviced regularly as well. Looking forward to your thoughts.

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Hello, thanks for the extra info. Your C70 definitely hasn't hit the high mileage yet, so this issue seems a bit unusual. But since you're seeing black smoke and a strong exhaust smell, it might be running rich - that's when it's burning more fuel than necessary. Keep in mind though, I’m no professional mechanic so make sure to get your car checked by a professional. But just from my experience with my 2004 Volvo S60, I recommend you check the oxygen sensors, as they help control the air-fuel mixture. If they're working fine, give the spark plugs a look-see. Faulty ones could be the reason why your engine's power is dropping. As for the check engine light, it could be so many reasons – but in your case, given the black smoke and the power loss, seems like something might be up either with the air intake system, fuel injection, or ignition system. Get these checked too. And about your thought on exhaust aftertreatment malfunction, in my case it wasn't the cause. But hey, every car is a different story, so it might not hurt to have it inspected as well. From your symptoms, it does seem like there might be a problem with exhaust parts as well. End of the day, I'm just sharing from my experience and what fixed the issue for me. Your local mechanic will be the best bet to find the issue accurately and fix it up. Hope this helps make things a bit clearer for ya, best of luck!

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Hey, that was pretty informative . Thanks a ton for laying it out for me. I'll follow your advice and first check out those oxygen sensors and spark plugs before moving on to the intake system, fuel injection and ignition system. I have my regular inspection coming up, so will make sure to get it all checked. It's bizarre how each car truly tells a different tale, but let's see how my story unfolds! Really appreciate your help though, fingers crossed this fixes my little beast. Cheers for now!

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