Air Suction Valves ASV With Cut-Off Valve: Notes

1985 Subaru GL 4D Sedan, 1.8 5, StandardSECTION Notes
  1. Remove ASV from engine. Without applying vacuum to section "A", blow compressed air through section "B" to see if a small amount of air is discharged from section "C". See Figure .
    Fig 1: Testing ASV with Cut-Off Valve
    G40363
  2. If too much air is discharged from section "C", reed valve is damaged or stuck open. Replace reed valve. If air discharge from section "A", diaphragm is broken. Replace air control valve.
  3. Apply 16 in. Hg to section "A". Blow air through section "B" to see if air flows smoothly through section "C". If air does not flow smoothly, reed valve is stuck closed. Replace reed valve.
  4. Blow air through section "C" to see if air flows through section "B". If air flows, reed valve is stuck open. Replace reed valve.
  5. If ASV has to be disassembled, inspect control valve by applying vacuum to the inlet vacuum port to determine if the control valve diaphragm operates normally and holds vacuum.
  6. Inspect the gasket for damage and cracks. After washing reed valve with gasoline, inspect for waves, cracks, or dents in the reed valve seat. Check for a cracked or broken reed valve. Inspect stopper for rust. Replace parts as necessary.
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