Emission Control Systems: Testing and Inspection

3MZ-FE EMISSION CONTROL: EMISSION CONTROL SYSTEM: ON-VEHICLE INSPECTION

ON-VEHICLE INSPECTION

1. INSPECT AIR FUEL RATIO COMPENSATION SYSTEM
(a) Put the engine in inspection mode Component Tests and General Diagnostics.
(b) Warm up the engine.
(c) Turn the power switch off.
(d) Connect the Techstream to the DLC3.
(e) Turn the power switch on (IG).
(f) Turn the Techstream on.
(g) Enter the following menus: Powertrain / Engine and ECT / Data List / AFS B1 S1, AFS B2 S1, O2S B1 S2 and O2S B2 S2.
(h) Warm up the air fuel ratio sensor with the engine speed at 2500 rpm for approximately 2 minutes.






(i) Maintain the engine speed at 2500 rpm and confirm that the displays of AFS B1 S1 and AFS B2 S1 are as shown in the illustration.

HINT:
- The illustration may differ slightly from the display on the Techstream.
- Only the Techstream displays the waveform of the air fuel ratio sensor.

(j) Confirm that the displays of O2S B1 S2 and O2S B2 S2 change between 0 and 1 V with the engine speed at 2500 rpm.
2. INSPECT FUEL CUT OFF / RESTART RPM
(a) Increase the engine speed to at least 2500 rpm.
(b) Use a sound scope to check for injector operating sounds.
(c) Check that when the accelerator pedal is released, injector operation sound stops momentarily (at 1800 rpm) and then resumes (at 1200 rpm).
Standard engine speed:






3. VISUALLY INSPECT HOSE, 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 improperly. Disconnection, looseness or cracks in the parts of the air induction system between the air flow meter and cylinder head will allow unmeasured air to enter and cause the engine to run improperly.

4. CHECK AIR TIGHTNESS IN FUEL TANK AND FILLER PIPE
(a) Press the lid switch to release the pressure in the fuel tank.
(b) Check that the lid opens.






(c) Disconnect the fuel tank vent hose from the fuel tank.
HINT: For information on the removal and installation of the fuel tank vent hose Removal.

(d) Connect the pressure gauge to the fuel tank.
(e) Apply pressure to the fuel tank to create an internal pressure of 4 kPa (41 gf/cm2, 0.58 psi).
(f) Check that the internal pressure of the fuel tank is maintained for 1 minute.
(g) Check the connecting portions of each hose and pipe.
(h) Check the installed parts on the fuel tank.
If any malfunctions, damage or other problems are found, replace the applicable parts, fuel tank, or filler pipe.
(i) Reconnect the fuel tank vent hose to the fuel tank.
5. INSPECT FUEL CUT OFF VALVE AND FILL CHECK VALVE
(a) Press the lid switch to release the pressure in the fuel tank.
(b) Check that the lid opens.
(c) Fill the fuel tank with fuel.






(d) Disconnect the fuel tank vent hose from the fuel tank.
(e) Connect the pressure gauge to the fuel tank.
(f) Apply pressure of 4 kPa (41 gf/cm2, 0.58 psi) to the vent port of the fuel tank.
HINT: Check the amount of fuel in the fuel tank. When the fuel tank is full, the float valve of the fill check valve is closed and no air can pass through.

(g) Remove the fuel tank cap, and check that the pressure drops.
If the pressure does not drop, replace the fuel tank assembly.
(h) Reconnect the vent line hose to the fuel tank.
6. CHECK AIR INLET LINE






(a) Disconnect the air inlet line hose from the charcoal canister.
(b) Check that air can flow freely into the air inlet line.
If air cannot flow freely into the air inlet line, repair or replace it.
(c) Reconnect the air inlet line hose to the charcoal canister.
7. INSPECT VAPOR PRESSURE SENSOR ASSEMBLY






(a) Inspect power source voltage of the vapor pressure sensor.
(1) Turn the power switch on (IG).
(2) Using a voltmeter, measure the voltage between connector terminals VC and E2 of the HV control ECU.
Standard voltage:





(3) Turn the power switch off.






(b) Inspect power output of the vapor pressure sensor.
(1) Turn the power switch on (IG).
(2) Press the lid switch to release the pressure in the fuel tank.
(3) Check that the lid opens.
(4) Remove the fuel tank cap.
(5) Using a voltmeter, measure the voltage between connector terminals PTNK and E2 of the HV control ECU.
Standard voltage:





(6) Reinstall the fuel tank cap.