Not too much about this in my haynes manual, I wish bentley made a 850 manual. Anyways, there are two tube coming out from an attachment on the intake right before the turbocharger. Its a small "Y" like fitting on the plastic intake tube. There is a small hard plastic tube running to it, which then connects to a rubber tube that fits on the joint. This is cracked, and it sounds like a vaccumm leak. I am unsure where the other end of the tube is. It runs under the intake manifold and fuel rail. I cannot find the other end. Anyone know what this is, and where it leads to? I will try to search around and be more specific. Thanks!