n80 valve

[andymc]

wat up peps i had my car pluged in to vag com the other day and it said i had a intermittent fault n80 valve sometimes open now i have heard about the n75 valve but not this one has any one got any ideas any help wil be much apprecited loving the forum

[B5A4Kevin]

the n80 is the valve sitting on top of your stock airbox with 1 electrical plug and a vacuum line on either side. fairly large and has a rubber housing around it usually. this is not the 1 way check valve downstream of it. the purpose of this valve is to allow unburned fuel vapor trapped in the charcoal filter to enter the combustion chamber via the intake manifold (all for the sake of emissions). a faulty one can cause mil, small evap leak, and rarely, even a lean condition. I've never used vagcom but with a 5051b/5052 (dealer scan tool) you can command the n80 (evaporative emissions purge valve) to come on. if you can do that, first listen for audible clicking. if it clicks it still could be bad. disconnect lines with it still actuating and electrically plugged in. try to blow in one side and see if it slowly lets air through (with each click). if it does then it is good and may have been temporarily clogged or had a temporary electrical gremlin. some intermittent/sporadic faults are semi normal. clear the faults and if it generates again, i would buy a new one. peace.

[djwimbo]

for Vag-Com go into "engine", -> "Output tests", and scroll through the tests. IIRC it's like the 5th one in the process.... I think.

[JohnBanks]

is it suppose to click? when working right, and it is consistent clicking.

[walky_talky20]

During the output test, yes. It will click steadily like once per second during the test. Same for the N75, injectors, etc.