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chengny · 07-19-2013, 07:19 AM

These might help:

The check valve is to prevent loss of vacuum (used to position the HVAC dampers) during times of low intake manifold pressure - i.e. at WOT.

07-19-2013, 07:19 AM	#4
chengny Registered User Join Date: May 2007 Location: New Hampshire Posts: 349	Re: vacuum hose for vents and defroster These might help: The check valve is to prevent loss of vacuum (used to position the HVAC dampers) during times of low intake manifold pressure - i.e. at WOT. Last edited by chengny; 07-19-2013 at 07:27 AM.