Corolla & Tercel

Blow air through each side of valve(s). On corolla and VTV 1 of Tercel, air should pass freely from side "B" to "A", but should pass with difficulty from side "A" to side "B". See Fig 1. On VTV 2 of Tercel, air should pass with difficulty from both sides.

Fig 1: Vacuum Transmitting Valve Test

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