Passport 2WD L4-2559cc 2.6L SOHC (4ZE1) (1994)
Air Injection Check Valve: Testing and Inspection
Remove Check Valve from Air Manifold. Test it for leakage by blowing air into the Valve from the Air Pump side and from the Air Manifold
side. If Check Valve is normal, air passes only from the Air Pump Side. If air passes from the Air Manifold side, it indicates the need for replacing
check Valve. A small amount of air leakage may be overlooked.