As above-what does it do & is this a common fault on 3.2`s-as I have now had 2 in 10 months? The Stealers could`nt really explain what it is??? Active Charcoal Filter-I can only assume it filters air in the inlet\breather ??? Any thoughts? The car now also needs 2 oxygen sensors aswell-and I always use V Power which I hoped help to prevent problems like this?...Thanx Wes.