The mass air meter is in the black plastic tube that connects to the air filter box.

It takes about 10-15 minutes to replace, and costs about $250-ish the last time I checked.

The throttle actuator sits underneath the intake manifold, and costs around $1,500.

With the questions you are asking, I suggest you take it in and have a mechanic that specializes in Mercedes.

Before you spend hundreds of dollars, it could be a simple vacum leak, i.e. cracked hose. There's a switch over valve at the front of the engine with a vacum hose that cracks from heat.

__________________
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".