Mini Cooper Engine Problems

Sounds like a defective EGR valve alright. I had similar symptoms (reduced engine power, check engine light, rough running) on my Mini Cooper. In that case, the EGR valve was gunked up with carbon deposits. Check if the valve is jammed in the open position. It's a common issue affecting vehicle emissions, not just diesel engines. Think of it like a clogged artery in your car's circulatory system. Have you checked for any error codes?

Thanks for the tip! Carbon deposits makes sense, especially since I do a lot of city driving. When your Mini had that issue, did you try cleaning the EGR valve, or did you just replace it? I'm trying to figure out if it's worth the effort to clean it myself before I commit to more extensive automotive repair.

I didn't attempt to clean the EGR valve on my Mini myself. I'm no expert, and messing with vehicle emissions components can be tricky. It's best to confirm the diagnosis properly. If you're experiencing all those symptoms – smoke, rough running, hissing – it's likely the EGR valve is completely shot. I'd suggest taking it to a trusted workshop for professional automotive repair. Better safe than sorry!

Just wanted to give you an update: you nailed it! Took my Mini to the shop and they confirmed it was the EGR valve, just like you thought. The automotive repair including parts and labor came to about 355€. Runs like a champ now, no more smoke, rough engine, jerking, or hissing. Fuel consumption is back to normal too. Thanks a bunch for your help!