Hi,

Thanks to all for the information I've already gleaned from this forum.

It has ben incredibly useful so far.

Just about to do a full service on my 55 plate M57 engined RR, and I bought a full kit with Maltings 4x4.

With the kit, I got an air filter, part number PHB000450, which I have searched and found it is a turbo vent air filter, but I'm still struggling to understand what this is actually for? If anybody could advise?

The kit does include the all important crankcase breather replacement filter as well, so happy on that front.

The turbo has variable vanes - so the turbo boost can be changed dynamically - and that is operated through a vacuum system. The filter is at the vent for that vacuum system. If you drive along with the driver's window down, and release the throttle, you'll probably hear a short 'chirp', which I think (but could be wrong!) is the vacuum system moving the turbo vanes and air either being expelled or sucked in through that vent.

Thanks dude.

I changed it so I know it's done, but I like to know what the various bits do on my cars.

Thanks for the explanation.