wel i have done a search for this and it seems that it could be that 'thing' that is attached to the top of the air box, but im just making sure.
Basically over the last few days, i have noticed that after i have driven sumwhere, while im waiting for the turbo to cool before i turn the engine off, i hear a ticking noise for roughly 20 - 30 seconds and then it dies away. The otherday i raised the revs slightly while it was doing it and it got quicker in time with the engine, i blipped the throttle lightly and it stopped the noise as the revs were dropping back to idle, but then started up again on idle (which makes me think its a possible noisy injector?) or does the 'thing' on the airbox have the same characteristics!?
its on a Z20LET engine by the way if that makes a difference