I recently bought a 2008 MCS Cabrio with 28,000 miles, it ran like a top for the first 2000 miles. I brought it in for the 30,000 mile service, and 2 days after picking it up while driving home it started to hesitate. The next morning, it idled very rough, and would cough and stall driving to the end of my driveway.

I had the car flat bedded to the dealer. After 4 days, they told me it was a bad ignition coil, they had replaced it and everything was fine. I picked up the car that night afterhours, and immediately upon starting, noticed it would not idle. It was running well enough to get home, but got progressively worse during the drive and the next morning would not get to the end of the driveway again. The symptoms were power loss, coughing and "bucking"

Called the tow truck back, car is back in. Car has now been in the shop for a week, dealer says every time they fix it, they test drive the next morning and problem reappears. They've been great about communicating with me but clearly they are stumped.

Latest report is: "pre-cat oxygen sensor wasn't working, and upon cold starts the vehicle was staying in open loop mode - dumping fuel/running rich; once warmed up, it adjusted accordingly."

The issue is that I never found the car to improve when the engine warmed up -- when I drove it home last time it was a 30 minute drive and the engine got progressively worse, particularly at higher RPM on the highway. When the problem first surfaced the engine was warm.

I'd hate to pick it up again and have to ride back in a towtruck for the third time. Anyone have any ideas?

 

It could be the infamous carbon build up "tar on valves" or the other... high pressure fuel pump HPFP.I've never experienced these problems on my '07 MCS,but it seems to be a problem on some '07-'10.Hope they finally resolve these problems as it is begining to give the highly respected Mini a negative tone...Good luck and hope they can resolve yours