Yes, it's very much a throttle, designed to lower the pressure in the intake manifold so more exhaust gas is sucked into the engine. Once EGR is disabled, you can clean up the intake and it will stay clean like mine. Later engines (1996 on) have a pressure sensor; the throttle plate cannot be removed or a code will be set, alas.

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970