Crankcase ventilation valve

**UrS4boy** · 11 August 2015, 22:30

AAN/ABY/ADU Positive Crankcase Ventilation (PCV) System with revised diagram, PNs and

Originally posted by Ivan_ZG

What exactly is that for, symptoms of malfunction and can it be removed and bypassed somehow? Does it affect anything?

They all affect something. Some more than others. And, in my environmental engineering opinion, should NOT be removed or bypassed.

Which one do you think it is:

AAN/ABY/ADU Positive Crankcase Ventilation (PCV) System with revised diagram, PNs and Links:

quattroworld.com Forums: AAN/ABY/ADU Positive Crankcase Ventilation (PCV) System with revised diagram, PNs and Links

http://forums.quattroworld.com/s4s6/msgs/22506.phtml

The Audi Enthusiast website. Forums for all Audis including A4, S4, A5, S5, A6, S6, allroad, A8, S8, TT, R8, Q5, Q7, 4000, 100, 200, v6, v8, vintage, local forums

**ColonialNomad** · 12 August 2015, 09:22

Originally posted by Ivan_ZG

What exactly is that for, symptoms of malfunction and can it be removed and bypassed somehow? Does it affect anything?

It's a useful thing.

http://www.s2forum.com/forum/showthread.php?t=77511&highlight=mystery+smoke

http://auto.howstuffworks.com/positive-crankcase-ventilation-system.htm

Crankcase ventilation valve

Crankcase ventilation valve

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