2009 MCS ~14,000miles
So I started to notice the engine sound like the turbo blow off valve was sticking open under acceleration. This past weekend I was driving on the freeway and noticed it when I was doing approx 50mph in 4th gear. I'd put the gas on the floor, and would hear right about 3 seconds of hissing before the hissing would stop and the acceleration would improve. I was able to repeat this a couple (2-3 times) and then figured I shouldn't make it have the problem on purpose, and just take it in this week for a check-up. I then got the CEL with an associated emissions warning on Sunday. Today, I took her to the grocery store, and the CEL vanished when I started it back up.

Anyone have any thoughts? I had the oil changed at about 10-11k miles when the dealer did the timing chain repair.

First appointment open was next monday and I need to put about 500-700 miles on her this weekend. Thoughts?

 

Well she's in the shop. We'll see what they come up with.

 

What was the resolution for this issue? My MINI is doing the exact same thing.

 

Ok, my apologies for failing to follow up with the crowd.

There was a loose intake manifold somewhere. I'm thinking it was after the turbo. The way the tech explained it, the turbo would kick in, there would be a massive air leak, and the computer would then shut the turbo down. I'm guessing what would happen was the turbo would go on, there would be a big leak, the mixture would be off, then when the turbo would shut down, acceleration would improve without the turbo.

When I got the car back, I was struck at just how powerful she was. It's amazing how the slow degradation of performance over time is hard to detect.

She ran like a completely different car when I picked her up.

 

Had my MINI in the shop today and the problem was resolved.

Just wanted to share the verbiage my service technician wrote up regarding the issue:

"THROTTLE BOOT CAME APART AT CONNECTION BELOW INTAKE. CHECKED FAULTS, FOUND HOSE CONNECTION LOOSE. RESECURED AND TEST DROVE. NO PROBLEMS FOUND."

My MCS has more power now than ever. I'm wondering at what point the hose loosened up. At 6K miles now. I'm wondering if it was ever right. Either way, the car drives like a rocket now. Totally different... and I'm liking it!