05CrewCab

Working on my first A6 and can't figure out what this broken part is in the close up picture. it's toward the back of the engine on the right side of the intake manifold. The hose is totally broken right before it T's into another part... 2002 2.7T

Thanks!

Nialist

That hose could be coming from one of the turbos. Then going to the N75 (wastegate control solenoid) Valve. Without that pressure reading, your N75 valve will not allow you to boost properly because it's sensing a differential in pressures between the 2 turbos. I have a "MacGyver" post on fixing this exact thing. Except the "t" was broken and not the hose. If you have to replace the hose, good luck. She's tight down by the turbos….

05CrewCab

Thanks you.

Is that round part in the pic the N75, or something else? That end of the connection has the vacuum. it looks like the T is part of that round part? the hose looks intact, thankfully.

boost401

its a 4way check valve

boost401

here its is http://www.ecstuning.com/Audi-C5_A6-...lve/ES2649617/

05CrewCab

Awesome! I cross-referenced that part number and found it at AutohausAZ for $12. Not too bad!

Thanks guys!

BeOhBe

Boost401 is correct, it's the 4-way check valve that connects to the turbo recirculating valve (N249). I broke that very same check valve last week while removing my PCV system. You can order just the check valve if you want, but there is a vac hose that is heat-shrunk (or glued maybe?) to it that you will find difficult to remove from the broken part without cutting and reattaching to the new check valve.
I actually ended up ordering p/n 078-145-733-G, which is both the check valve and the attached vac hose. I got mine from ECS, though when I searched for the above complete part, it said it wasn't a match for my '04 2.7t... but it is. Here's a photo of old vs new:



And a picture of the bag with p/n that it came in from ECS:



You can find photos I took of it in my 2.7t here:
https://www.audiworld.com/forums/sho....php?t=2863692

Cheers!

05CrewCab

Ah, that pesky plasticky hose... thanks to your advice here, i took a torch and lightly hit it with heat at the connection and the T slide right out. warmed it up again when installing the new T and it slide right in. Thanks!