LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 1981 >> Pickup Base >> Repair and Diagnosis >> Engine Mechanical >> Auxiliary Emission Control Systems >> Air Injection System >> Testing >> Vacuum Control Valve (VCV) >> Corolla
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Vacuum Control Valve (VCV): Corolla

  1. Start engine and run at idle speed. Disconnect vacuum hose from and connect vacuum gauge to port Z of VCV 1. Check that gauge indicates about 7.9 in. Hg. Reconnect hose.
  2. Disconnect vacuum hose from port Y and Z of VCV 2. Check that a small amount of air flows from port Z to port Y. Disconnect vacuum hose from port S. Check that air flow increases. Reconnect hoses.
  3. Disconnect vacuum hose from port S and Z of VCV 3. Plug port Z with finger and check that no vacuum is felt. Reconnect hose to port S. Vacuum should be felt momentarily. See Figure.
scientia non olet · About LEMON Manuals