My guess is not that the pump itself has seized, but rather the pulley bearing.

Mercedes sells a rebuild kit for the pulley and bearing in the low $200 range.

You can buy it at the dealer.

You remove the air pump from the car, install the new pulley and bearing, and re-install.

__________________
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".

Hey Paul!

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Maxwell -- look at my post from last week. Just did an a.i.r. pump replacement on my '95 E320. Told the whole story.

Good luck.

Hey Chris, I saw the write-up. Good job.

__________________
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".