Tappet noise

[Dosco]

Tapping noise

.... although it isn't the tappets but a small valve like device sitting right next to the fuel injection pump. It has the letters MOT on it and has two pipes attached one black (hard) plastic and the other feels like reinforced rubber.

After a few moments ticking over this device emits a loud clacking noise as if a valve is opening and shutting very fast, 'sounds like' a 50 caliber machine gun.

So what is the device and why would it make such a racket albeit intermittently in the main during extended engine tick over

1998 W210 (E240) Petrol

 

[bibamus]

I think this is the purge valve, part of the emissions system. Although i dont think it causes any problems, I have heard it can be cleaned, but ideally, a replacement should get rid of the noise.
Allan

 

[Dosco]

I think this is the purge valve, part of the emissions system. Although i dont think it causes any problems, I have heard it can be cleaned, but ideally, a replacement should get rid of the noise.
Allan

Cheers Allan, thanks for the info.