Need to ident. a part
 

Hi
Im trying to find out what this part is and what it does.
The car is a 1975 450 sl
This piece is mounted on the intake manifold next to the cold start valve.
It is a Bosch 0 280 140 017.
Looks to be some sort of a thermostat .What is it
What does it do, and how do i know if it works
Is their any way to test it?????
Thanks
Bob

That is the warm-up auxiliary air valve! Supposed to raise the idle speed when the engine is cold.

Re: part id
 

d.o.c.

Thank you

Bob