What is/was this valve thing on top of my airbox?

**cjonesgo** · 08-06-2008 02:02 PM

I have a little gulp valve or something connected to an elbow pipe on top of my airbox that I would guess to be part of emissions system.
The rubber on it is split an it looks a bit melted so I cannot read any numbers on it. It is obviously leaking something. What is this thing? Anyone have a part number? I want to get a new one before I head out on a road trip tomorrow. Help!

My camera is dead so I'll take a pic as soon as the battery charges. Thought maybe someone might know what it was off the top of their head...

Gray and Black(rubber) pressure valve of some sort. Directly on top of air filter box. Connected to an elbow pipe.

**AudiA4Turbo22** · 08-06-2008 02:07 PM

if it has a connector plugged in to it it is ur N80 valve, and i have one if u want it, if it looks like a small saucer that is gray and white it is a check valve. A new N80 purge valve is $110 but if u want one PM me.

**pondside36** · 08-06-2008 02:08 PM

I beleive that is part of the evap system.. but a pic may help peolpe tell you exactly what it is.. GL

**AudiA4Turbo22** · 08-06-2008 02:12 PM

which one is it? letter A?

**cjonesgo** · 08-06-2008 04:09 PM

ok, had to run an errand, but was able to snap a pic with my phone. camera appears to be all the way dead...

crappy pics, but they should get the idea across.

AudiA4Turbo22:
Doesn't appear to be any of the letters shown. My car is an 02 if it would make any difference, but I can't see how it would. it is a Black (rubber) and Gray (plastic, maybe used to be white?) and looks like a saucer, but I don't see it in the picture.

**widgget** · 08-06-2008 04:13 PM

thats the check valve. you can get those pretty cheap.

**old guy** · 08-06-2008 04:14 PM

Check valve. Part # 058 905 291

**cjonesgo** · 08-06-2008 04:15 PM

old guy to the rescue. thanks!

**Teratorn** · 08-06-2008 04:52 PM

I think there's about 5 more in various places that you might want to check the condition for. I had to replace that same one on the photo and that was causing rough idling for me and some hesitation on 1st gear. I think it's $18 on ECS.

**cjonesgo** · 08-06-2008 11:12 PM

unfortunately I had to have one today as I am leaving on a trip in the morning. $39 at the audi dealership. ugh. vw dealer was $43. no dice at kragen, napa, autozone...

expensive little thing. it's just a one way valve and if i seal up the cracks in my old one, it still works fine so at least i'll have a spare. think that this may affect mpg? i was getting not horrible, but not great mileage. i put in new plugs, k&n filter, new battery and fixed this little valve so hopefully something makes a difference.