I have an 08 MCS with ~24k miles on it. Started my car this morning and the engine malfunction indicator (yellow outline) came on and stayed lit during entire commute. I wasn't sure what the indicator meant so I checked the manual and it read something like, "Full engine power not available, you may continue journey but have engine checked ASAP..." The engine also sounded terrible at low RPM's even after warming up in driveway for about 5 minutes.

I live in Cincinnati where it is currently 13°F and has been below freezing for over a week now. I am forced to store the vehicle outside and park outside at work. This is the car's second winter and I had no issues last year. Anyone out there with similar symptoms? Is this a cold weather issue or something of greater concern?

I haven't called the dealer yet but will today. Thanks for the help!

 

At least it's not the half power "limp mode". I know even my R56 sounds a bit diesel-esque on startup even after the cold start chatter fix. Just take it to the dealer and let them do the work. Hopefully you're still under warranty.

 

Probably only one of the input sensors to the engine computer is malfunctioning due to the weather. Not an immediate problem if its yellow. Take the car into the dealer when possible.

 

Sounds like the same thing my car has been doing. I noticed that it only did it when I had less than 1/4 tank of gas. I filled up yesterday morning and it seems to be working good so far. Maybe there is bad gas in the tank? Either way, I made an appointment for the dealership tomorrow.

 

I had the yellow light come up right after the first big freeze here and it simply turned out to be a misfiring spark plug.
Could have happened at any time of year.