Mini Cabrio Check Engine Light Air Valve Suspected

Sounds like a potential air valve issue. I had a similar problem with my Mini, same engine. The check engine light was constantly on. Have you checked your manifold pressure? Sometimes a leak in the vacuum hoses can cause engine stalling, especially around the throttle body.

Manifold pressure, huh? I'm not really sure how to check that myself. And vacuum hoses? Where exactly are those located, and what should I be looking for? I am worried about engine stalling.

Yep, that's exactly what happened to me. The hoses can crack or become loose over time, causing a vacuum leak. Honestly, unless you're comfortable working on engines, it might be best to take it to a workshop. They can do a smoke test to find any leaks in the vacuum system and properly diagnose the air valve.

Just wanted to let you know that you nailed it. Took my Mini Cabrio to the shop, and they confirmed it was a defective hose connection from the pump to the air valve. Total cost came out to 175€, which is annoying, but at least my check engine light is off. Thanks again for the help!