C220, serious problem.

Hello everybody. I came here to ask some question about my car, because nobody else can answer, so i hope somebody here had a same problem and know how to resolve it. The matter is, that my car is shaking very strong  when i slow down, the idil is going up and down from 7K-12K, engine can shut off, and do not turn back within 3min-1 hour. Most of times it is happening near the crosswalks, when i slow down for red light. "Check engine" light is coming , speedometer is dieing. Sometimes computer is showing a code "mass air flow system incorrect". I went with car to the diller, he examed car and said that i need to change all electrisity in the car. I did it, but it didnt help, so diller do not know how to help me.

May be somebody knows this problem, and how to resolve it?