Hey there! I can totally relate to your issue. I have a 2013 Volvo XC90 and faced a similar problem a while back. It turned out that the Fuel Pressure Regulator was defective and replacing it did the trick. It was a fairly serious issue. The black smoke you're seeing is due to incomplete combustion. And yes, it could definitely be due to more fuel getting injected than required, which can happen if the regulator isn't doing its job right. My car was also having cold start and power issues, just like yours. At the garage, the mechanics did an in-depth diagnostic and identified the problem. After replacing the fuel pressure regulator, they also did a few test runs to make sure that the problem was fully resolved. And, it was. The smell was also gone post repairs and the engine light turned off. My car was back to normal and driving it felt the same as before, if not better. So, it's worth checking the Fuel Pressure Regulator on your XC70. Hope you get your ride fixed soon! Cheers.

(Translated from German)

Hey! Thanks for sharing your experience with your XC90! Your description hits the nail on the head - it's exactly what I've been going through. I'll definitely have a look into that Fuel Pressure Regulator issue. By the way, if you don't mind me asking, can you recall roughly how much this kind of repair set you back? And have you noticed anything peculiar with your ride since the fix, like any new symptoms cropping up? Always good to know what could potentially be down the road. Cheers!

(Translated from German)

Hey! I'm glad my previous experience could give a bit of insight for your Volvo troubles. So about the repair cost, for the fuel pressure regulator issue, it did set me back by 250 Euro. But hey, thinking about it, seems like a fair trade-off for not having my ride belch black smoke anymore, right? Since getting it fixed, I haven't had a single problem with the old bird. That issue with the mixture control and it being overly rich? Sorted. The mechanics did a bang-up job, and it shows. It's running just as fine as when I first got her. Here's hoping your ride gets back on track soon too! Cheers!

(Translated from German)

Hey! Thanks for the quick response and all the useful intel. And yeah, 250 Euro sounds like a fair price to get rid of these troubles and have the old girl running smooth again. Glad to hear yours is performing well post-fix, that's reassuring! I've scheduled an appointment with my mechanic this week. I'll make sure to point them towards the Fuel Pressure Regulator. Hoping it all works out and my ride gets back in shape. You've been a great help. Thanks again! Ride safe. Cheers!

(Translated from German)