Air Cleaner Cap Sub-Assembly (ES300)
WARNING: This page is about a different car, the 2002 Lexus RX 300 and 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
Cover port "C" with finger, and check that air flows from port "B" to port "A". Cover port "C" with finger, and check that air does not flow from port "A" to port "B". Cover port "A" and "C" with fingers, and apply 18 in. Hg (60 kPa) of vacuum to port "B", and check that there is no change of vacuum after one minute. See Fig 1.