Evaporative Emissions System: Testing and Inspection

INSPECT EVAPORATIVE EMISSION CONTROL SYSTEM
a. After starting the engine, disconnect the vacuum hose shown in the illustration.
b. Confirm vacuum occurs at the VSV port, when choosing "ACTIVE TEST" and "PURGE VSV" according to the display on LEXUS hand-held tester.
c. Finish "ACTIVE TEST", then connect the vacuum hose again.
d. After going to "ECU DATA MONITOR" on the hand-held tester, choose "PURGE VSV" to check the operation of the purge VSV.
e. After warm up the engine and drive the vehicle, confirm the VSV turns on from off.





VISUALLY INSPECT HOSES, CONNECTIONS AND GASKETS
a. Check for cracks, leaks or damage.

HINT: Separation of the engine oil dipstick, oil filler cap, PCV hose, etc may cause the engine to run out of turn. Disconnection, looseness or cracks in the parts of the air induction system between the throttle body and cylinder head will allow air suction and cause the engine to run out of turn.





INSPECT FUEL TANK CAP
a. Visually check if the cap and/or gasket are deformed or damaged.