Your car may be different, but in my W124, it's behind the passenger side vent.

The dealer sells little sticks that you insert into each side of the vent. There are tabs that the sticks go into. You pull the tabs toward the center of the vent, and the vent pulls right out. You can reach in with your hand and pull the motor out.

You can use any long, thin object with a pointy end, like an awl, ice pick, skewer, etc. in place of the dealer tool.

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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".