# 81 210 anti backfire valve



## biztyke (Jan 31, 2008)

theres a part that is connected to the air cleaner housing on my 1981 datsun 210, and it has two other hoses that have been disconnected(by previous owner) and where they were connected is now plugged/sealed with rubber fittings

after some research i have found that it is an anti-backfire valve. any reason why it would be disconnected? is it ok to leave it off? suggestions?


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## smj999smj (Jan 1, 2006)

The only reason to plug it off would be if it didn't work and they were too cheap to fix it. The anti-backfire valve is part of the secondary air injection system and is used to reduce emissions. The small nipple goes to the intake manifold vacuum source. The medium sized fitting is for the air discharge to the intake manifold. The largest fitting is an intake for air from the air cleaner. I would re-hook it back up and see if it works. To test the AB valve:

With engine at operating temperature, remove air cleaner. 
Disconnect inlet hose from AB valve and place finger near opening in valve. 
Run engine at approximately 3,000 rpm and quickly release throttle. 
If suction is not felt at opening replace AB valve.


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