Anyone know what this switch does ?
 

I was doing a mid summer engine deatil and noticed a switch on the 300E right where the throttle cable linkages are. It does not seem to take much to open it so I figured that possibly it might bring the engine out of idle mode of some sorts. Just wondering if anyone could clear up what this part does.

A photo would be useful. Might be the overrun cut off switch (tells the fuel system to shut off the fuel when the throttle is released if engine revs over about 1200 rpm.

Sounds like the closed throttle position switch (CTP) to me.
Gilly