Mercedes B Klasse Hybrid Engine Trouble

My 2021 Mercedes B Klasse hybrid is acting up. The check engine light is on, it stalls at idle which is super annoying, and it feels like I'm driving with half the power. Mileage is at 178456 km. Could it be the fuel volume regulator? Has anyone else experienced this? Could a faulty high pressure pump cause this? Any thoughts on how to keep it running until I can get it looked at? I'm also seeing a drop in fuel efficiency, and I suspect engine misfire.

4 comment(s)

That sounds familiar. I had something similar happen with my B Klasse, though I don't remember the exact mileage. Rough idling and reduced engine power, yep. Did you notice any difference in your fuel economy before all this started? It could be the fuel pump, but have you checked for any other obvious things like a loose gas cap?

Fuel economy definitely took a hit, I should have mentioned that. Gas cap seems fine. What exactly was your issue? Was it the fuel volume regulator in the end? How much did the repair set you back?

Yeah, mine was a defective fuel volume regulator too. Check engine light, rough idling, the whole shebang. Honestly, I wouldn't mess with it too much yourself. It could cause more damage. Get it to a workshop. It's probably the high pressure pump that's defective, and it's not a cheap repair.

Thanks for the heads up! I took it to the shop, and you were spot on. Fuel volume regulator was bad. New high pressure pump, the whole thing. It cost me 1510€, but at least it's running smoothly again.

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