Hi guys,

I notice on some occasions when starting my E230 (M111) when cold I hear this random clicking from behind the glove box area. Sounds like a relay switching, except it continually clicks for 30 seconds or so.

You have a RHD so the glove box is on the left of the car, correct?

If that's the case then most likely it is the purge valve. To confirm lift the hood and locate the purge valve, it's forward of the spring tower, black, about 30mm in diameter with hoses and wires coming to it. On the top it says MOT. Then have someone start the car and see if that's where your noise is coming from (you can also put your finger gently on it and feel it working).

If that's it, it's really nothing to worry about (it runs on startup to purge the evap system), but cleaning can help quiet them down. Unplug hoses and connection, blast with aerosol carburetor cleaner and shake out, repeat a few times. Use eye protection and work in a well-ventilated area away from fires/flames. Let it dry out for ten-fifteen minutes before reinstalling.

Yep, i'm familiar with that. I'll have a look on the weekend. But murphys law means it hasn't happened since I heard it the other day!