Just got my 07 MCS back from the dealer. They repaired timing chain tensioner and reflashed computer. Car has had a shutter at idle speed since I got it back. Today the engine cuts out (misfires) under load. Check engine light flashes but go out. Later it is running rougher and now the check engine light stays on. Idle is very rough. Appears to be skipping a cylinder or is in limb mode.
Car has 32k miles on it and just ran out of the time warranty LAST WEEK.

 

I would take it back and explain that it was not doing it before they touched it.

 

i think you have a good case where they will fix your problem under warranty. certainly, this is related to the repair they did under warranty. call them and take it back ASAP. i've read posts where dealer will still fix these type of problems under warranty even when you're out of warranty since it's only been a week.