HUGE thanks for the picture from me. I'd given up looking and concluded that this '89 w126 500SE didn't have such a switch at all. Which was a damn shame because the engine behaviour suggested that if there was one, it wasn't working.

Now, thanks to you, I've found the stoopid thing - and it isn't working!

Well, it's intermittent: it operates if you let the butterfly snap shut, but letting it close gently usually doesn't close the contact.

My question now - before I go burrowing into the engine to get my hands on it - is what am I in for if this can't be resurrected? Do I have to replace the entire Throttle Body, or can I get the switch separately?

Anyone have a clue? I'd be very grateful for any info.

CD