Whats this? and rattle on startup.

[abimogen]

IMG00342-20110205-1319.jpg

What is this? It starts clicking/ticking after the car has been idling for a couple of mins. It looks like some kind of valve that sits on top of the airbox, it has siemens stamped on it.

Also, on start up I have a rattle, almost like a chain. It goes after a second or 2. Should I be concered?

Thanks

[olds_kool]

pic is n80 purge valve, something to do with emissions? but it is supposed to tick

cant help with rattle sorry

[Crasher]

The ticking from the EVAP valve is normal and nothing to worry about, in fact I get so fed up with customers fretting about this I have begun to wish VAG would have attached a label to the valve saying something like “yes it should tick, don’t worry about it”. The rattle on start up will b the relay chain between the cams and this can be the result of the oil being too thick, the wrong oil filter, the cam chain and/or tensioner being worn or even a low oil pressure issue, especially if it is a 1.8T.

[abimogen]

Ok, thanks, glad it's meant to be doing that.
It's just a 20v N/A, would an oil and filter change cure the rattle problem?

[Crasher]

Possibly, use 5w/40 oil.