I have my first Benz. Used 2003 SLK230. It has been a problem from day one. I have chased a number of problems and made fixes but still have persistent issues. Found a couple vacuum leaks and changed out all vacuum lines. I consistently get a P200b-000 error code but no check engine light. After warm up I get idle rpm hunting. My fault counter shows cylinder faults across all cylinders. Not a lot but faults are consistent. Tons of oil in the left side intake when bought but all has been fixed. Was rebreather piping and been replaced. Dealer put in new Bremi MAF but not sure if it is doing the job as well as OEM. O2 sensors read well. I did new plugs just because. Injector started leaking so I replaced all injectors. Past owner had the ignition upper harness changed out. I have replaced all right side breather hosing too. Oil separator and attached parts are working well and no oil. I am stumped. Any ideas? Can anyone provide more detail information on the above trouble code???