Seeking Advice on 2019 Volvo S90 Gasoline Issues: Black Smoke, Engine Shut-offs, and Poor Mileage

Hey there, I've got a 2017 Volvo S60 and I've faced a similar issue. I don't claim to be a pro with cars, but I have some experience messing around with them. Bit of a backstory, I had to take my car to my trusted workshop as it was acting funny, similar symptoms to what you're describing. They diagnosed that a cable/plug was defective and its replacement cost was around 95 Euro. The replacement sorted the problem for me. With your S90, it could be the same issue. Although, I'd recommend having it checked out by a professional just to make sure. Could you possibly give more info on your car's history? Did it recently have any work done on it? Any extra details could be useful to understand what's going wrong.

(Translated from German)

Hey, thanks for your input. Honestly, I'm not a pro either, just trying to figure this stuff out. As for recent work, no, there's been no major service done recently. The last one was at 137802 KM, just regular maintenance and oil changes, no components replaced or anything. 95 Euro isn't so bad for the fix, that gives me some hope. I'll take your advice and get it checked out by a pro though, better safe than sorry I guess. Thanks again for your help!

(Translated from German)

No worries at all, it's good to share some wisdom where I can! We're all here learning and sorting these things out. You're right about 'better safe than sorry'. Especially with the range of symptoms you described, they could potentially indicate several different things, from a bad fuel mixture to worn spark plugs or even a damaged catalytic convertor. The fact that you haven’t done any major work recently is good to hear, but unexpected things can happen, even with regular maintenance. Can't deny cars have their mysterious ways, right? The good news is, with the check engine light on, a professional should be able to tap into your car's computer to get a more precise idea about what's wrong. And if it happens to be just a faulty cable, like mine was, the cost isn't sky-high. But hey, even if it turns out to be something more, at least you're getting to grips with it sooner rather than later. Keep us posted on how it goes at the workshop! It's always good to learn from each other's experiences. Best of luck with it!

(Translated from German)

Hey, your words are seriously reassuring! Yes, cars do have their own temperament, don't they? I'm gonna book an appointment at the workshop and see how it goes. Hopefully, it's just a cable issue like you experienced. Got a knot in my stomach thinking about serious repairs, but you're absolutely right, better to know what we're dealing with sooner. I'll update you guys once I hear from the pros. Thanks for the vote of confidence!

(Translated from German)