Evaporative Emissions System: Testing and Inspection

REMOVE EXHAUST TAIL PIPE AND HEATED INSULATOR
INSPECT LINES AND CONNECTORS
Visually check for loose connections, sharp bends or damage.







INSPECT EVAP SYSTEM LINE
a. Warm up the engine and stop the engine.

Allow the engine to warm up to normal operating temperature.

b. Install a vacuum gauge (EVAP control system test equipment vacuum gauge) to the EVAP service port on the purge line.







c. TOYOTA hand-held tester:

Forced driving of the VSV for the EVAP.
1. Connect a TOYOTA hand-held tester to the DLC3.
2. Start the engine.
3. Push the TOYOTA hand-held tester main switch ON.
4. Use the ACTIVE TEST mode on the TOYOTA hand-held tester to operate the VSV for the EVAP.







d. If you have no TOYOTA hand-held tester:

Forced driving of the VSV for the EVAP.
1. Disconnect the VSV connector for the EVAP.
2. Connect the positive (+) and negative (-) leads from the battery to the VSV terminals for the EVAP.
3. Start the engine.







e. Check the vacuum at idle.

Vacuum: Maintain at 0.368 -19.713 in.Hg (5 - 268 in.Aq) for over 5 seconds

HINT: If the vacuum does not change, you can conclude that the hose connecting the VSV to the service port has come loose or is blocked, or the VSV is malfunctioning.

f. If you have TOYOTA hand-held tester:

Conclude forced driving of the VSV for the EVAP.
1. Stop the engine.
2. Disconnect the TOYOTA hand-held tester from the DLC3.

g. If you have no TOYOTA hand-held tester:

Conclude forced driving of the VSV for the EVAP.

1. Stop the engine.
2. Disconnect the positive (+) and negative (-) leads from the battery, and from the VSV terminals for the EVAP.
3. Connect the VSV connector for the EVAP.

h. Disconnect the vacuum gauge from the EVAP service port on the purge line.
i. Connect a pressure gauge to the EVAP service port on the purge line.







j. Check the pressure.
1. Close off the air drain hose at the marked position of the canister with a hose clipper or similar instrument.







2. Add the pressure (13.5 -15.5 in.Aq) from the EVAP service port.

Pressure: 2 minutes after the pressure is added, the gauge should be over 7.7 - 8.8 in.Aq.

HINT: If you can't add pressure, you can conclude that the hose connecting the VSV-canister-fuel tank has slipped off or the VSV is open.







3. Check if the pressure decreases when the fuel tank cap is removed while adding pressure.

HINT: If the pressure does not decrease when the filler cap is removed, then you can conclude that the hose connecting the service port to the fuel tank is blocked, etc.

k. Disconnect the pressure gauge from the EVAP service port on the purge line.