Geeze! The new replacement MAS did not correct the problem. After I drove the car several more miles after work this afternoon, the Check Engine Light returned.
P2016 Self adaptation of mixture formation from bank1/2 of cylinder is at
P2085 max/min limit at part throttle
Since I dont have the tools to check the fuel pressure, and the mileage is 61,000, I'm going to proceed with changing the FUEL FILTER. It is my understanding the fuel filter on the 2001 CLK320 has the fuel regulator build into the unit. I don't mind "throwing" money at maintenance items.
I'll also planning to check the voltage values on the O2 sensors.
FYI.. I purchased this car because I was tired of working on my 400se all the time - Never a dull moment when you own a Mercedes