Hi folks, my 2012 1.6 tdi has a fairly rapid ticking noise (fast heart beat speed) coming from in and around behind the dash when the engine is at idle.

I've tried changing all the fan / ac / recirculate options and nothing changes but at about 1500 rpm the noise stops so I'm guessing its engine related, whats weird is it can't be heard in the engine bay!

I'm pretty sure the noise started after the last service when the Emissions mod was carried out, the garage had a listen and said it was nothing to worry about!!

Thoughts?