I have an 07 525i, and since this past saturday the engine is making a clicking noise, and increases when i rev the engine.
Does anyone have an idea of what it might be?

 

I have the same clicking noise on my 05/2008 built bought new in December 2008.

I noticed this and thought maybe my heavy foot is the reason to this ticking... I pop'd ma hood nothing suspicious but Im no tech. Ive been to the service when the time came my car has now 11,XXX Km on the dial still fresh. I've added oil about 3 times before I took in for service. The engine tick still continues but I take no notice plus my changed exhaust take all the attention now for sound! Love it!

 

Check for SIB 110907 or look for "HVA" using the search function ... the search is your friend.