I went through the same ordeal you are going through.

I even purchased the throttle actuator and it didn't fix the problem.

Took the car to the local MB dealer, and they diagnosed a vacum leak at the intake manifold, and it fixed the problem.

A vacum leak can make it look like you have a bad MAF and / or throttle actuator.

__________________
Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".