It is not clearly visible but it is either the breather tube or the breather hose. Since you said it is a pipe, I am sure it is the breather hose.

 

Does it look like the 's' shaped hose in this kit? Home Page > Search > Breather Hose Kit > ES#5942 Crankcase Breather Hose Refresh Kit - 058198298 If so it's the crankcase breather hose, known to crack due to the hot/cold cycles the engine goes through.. Mine was cracked when i got mine, not to hard of a fix.

 

Wow, I think that's what it is!

Thanks for this guys!

 

And as someone who has recently replaced the breather hose assy, I can tell you it is the least amount of fun you will have with your Passat. I didn't want to remove the intake manifold, so ended up having to cram my hand(s) down in there to remove the clamps, hose, valve; install the new ones, and tighten up the new clamps. Took my hands a week to uncramp, and two weeks for all the scratches and gouges to heal on them.

Suggest removing the manifold if you can. It's just so much easier with it out of the way.

 

Don't get me started on how much fun this passat has been! I'm sure there is a specific area for complaining...

Ok here's my top 3 so far:
1. If you unlock the car but don't open the driver door within 3 sec the alarm reactivates itself. Got your hands full of groceries that need to go in the trunk? you'll need to take them to the driver door first or opening the trunk will set off the alarm!
2. Drive up to the window in a drive thru with the window half way down. I need to reach out the window to get the food so I press down on the button. Apparently if you press down too quickly IT ROLLS THE WINDOW UP which pins you with your arms out the windows!
3. Whoops the battery died, no problem well just go buy a new one...easy! Until you put the new battery in an it still won't crank because the stupid thing forgot its own engine codes to operate when I unhooked the battery! It remembers my radio stations, but not how much air/fuel to mix! That one actually cost me $1000 because the codes wouldn't "take" so we had to buy a whole new whatever it's called...after being towed to the dealership!
Bonus 4. The day I bought this car the passenger window regulator imploded and the whole window burst inside the door...as I parked it in the driveway!

Actually I'm going to check to see if there is a venting forum because I have too many lemon stories not to share!

 

Just wanted to follow up and say that I got this part and was able to put it on with just a flat head screwdriver and box knife. Took me hours of hard choking the car to get my hands under the intake manifold enough to just take the broken pipe out and get the rubber gaskets off. As I put them back on, I learned the secret to the order in which they have to be put on...

So here's what I did: Attach the biggest/bottom part of the rubber T over the bottom pipe and tighten the clamp. Press the right side of the T (now at the end of the bottom pipe) to the pipe in the back of the engine and tighten that T, thread the twisted breather pipe that shattered through all of the hoses that I am too stupid to have removed before hand and put the rubber gasket on the bottom part, then press it firmly into the hole until it seats, put the metal clip into the slot on top of the place you slid the pipe into, now the fun part, put both of your elbows together and lean over under the manifold to get your hands as deep as possible to press the breather hose into the left side of the T, use your right hand to press against the back of the T to get it to actually go into the miniature opening, tighten the the final clamp. Reattach the coolant tank.

Took me 3 hours total/straight working with a screw driver, a box knife, a mouth full of profanity, and a small brain.

Thanks again to everyone for spotting the part and helping me locate the fix!

 

Nice man! Props to you for doing it with the Mani still on for your first time.. It's hard enough with it on! I had to change the housing assembly - the part that is directly attached to the crankcase and that has the breather hose go into it and i left the manifold on. Imagine that!