My friends mk4 tdi has started making a crazy ticking noise, I'm pretty sure its coming from the part pictured below. It sounds like a relay opening and closing very quickly, like about 10 times per second. So basically what is that part? (im guessing something ignition related judging by the number of wires going to/from and that it keeps going about a second after the engine stops) and does any one have any idea why would it have suddenly started getting noisy? Thanks guys!
by no means an expert opinion, but the ticking you describe sounds like it could be the charcol chamber that monitors emissions. its located on left hand side of engine bay. normal noise. find exactly where its coming from. but yea, that looks like n75 valve which shouldnt be ticking.
