On-Vehicle Inspection
ON-VEHICLE INSPECTION1. INSPECT AIR-FUEL RATIO COMPENSATION SYSTEM
a. Measure the voltage between the terminals of the ECM connectors.
NOTE: Connect test leads from the back side of the connector. The connectors should not be disconnected from the ECM.
HINT: The voltage between the terminals of the ECM is kept constant regardless of the voltage of the A/F sensor.
b. Connect the hand-held tester to the DLC3.
c. Turn the ignition switch to ON.
d. Select the following menu items : Data List / A/FS B1 S1 and O2S B1 S2.
e. Warm up the A/F sensor with the engine speed at 2,500 rpm for approximately 2 minutes.
f. Keep the engine speed at 2,500 rpm and confirm that the display of "A/FS B1 S1" is as shown in the illustration.
HINT:
- The illustration may slightly differ from the display on the hand-held tester.
- Only the hand-held tester displays the waveform of the A/F sensor.
g. Confirm that the display of "O2S B1 S2" changes between 0 and 1 V with the engine speed at 2,500 rpm.
OK:
The voltage output oscillates more than 8 times in 10 seconds.
CAUTION:
- Perform the check immediately after warming the engine up.
- If the voltage variation could not be verified, warm up the heated oxygen sensor again. If it could not be verified even after warming up the sensor again, check the DTC No.
2. INSPECT FUEL CUT OFF RPM
a. Increase the engine speed to at least 3,500 rpm.
b. Use a sound scope to check for injector operating sounds.
c. Check that injector operating sounds stop momentarily and then resume when the throttle lever is released.
3. VISUALLY INSPECT HOSES, CONNECTIONS AND GASKETS
a. Check the appearance.
1. Check if the indicated portions of the engine assembly are cracked, leaking or damaged.
HINT: Disconnection of the engine oil level gage, 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 throttle body and cylinder head will allow air suction and cause the engine to run improperly. If necessary, repair the engine assembly.
4. INSPECT EVAP SYSTEM LINE
a. Warm up the engine and stop the engine. Warm up the engine to normal operating temperature.
b. Install a vacuum gauge (EVAP control system test equipment vacuum gauge.into the EVAP service port on the purge line.
c. When using a hand-held tester: Operation of VSV of EVAP using hand-held tester.
1. Connect the hand-held tester to the DLC3.
2. Start the engine.
3. Turn the hand-held tester ON.
4. Select the following menu items: DIAGNOSIS / ENHANCED OBD II/ ACTIVE TEST / EVAP VSV (ALONE).
d. When not using a hand-held tester:
Operation of VSV of EVAP not using hand-held tester.
1. Disconnect the VSV for EVAP connector.
2. Connect the positive (+) and negative (-) leads of the battery to the VSV for EVAP terminals.
3. Start the engine.
e. Check the vacuum when the engine idles.
Vacuum:
Maintain at 0.368 to 19.713 in.Hg (5 to 268 in.Aq) for over 5 seconds.
HINT: If the vacuum does not change, the hose connecting the VSV to the service port is loose or blocked, or the VSV is malfunctioning.
f. When using a hand-held tester: Conclude operation of VSV of EVAP using hand-held tester.
1. Stop the engine.
2. Disconnect the hand-held tester from the DLC3.
g. When not using a hand-held tester: Conclude operation of VSV of EVAP not using hand-held tester.
1. Stop the engine.
2. Disconnect the positive (+) and negative (-) leads of the battery from the VSV for EVAP terminals.
3. Connect the VSV for EVAP connector.
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. Prepare a rubber hose that has an inside diameters of 15 to 18.5 mm.
2. Disconnect the atmospheric side hose of the pump module.
3. Connect the prepared rubber hose to the pump module, and pinch the rubber hose with the clip to prevent air from entering into the canister passage.
4. Apply pressure (13.5 to 15.5 in.Aq) from the EVAP service port.
Pressure:
The gauge should still read over 7.7 to 8.8 in.Aq for 2 minutes after the pressure is applied.
HINT: If you cannot apply pressure, the hose connecting the VSV, charcoal canister and fuel tank has slipped off or the VSV is open.
5. Check if the pressure decreases when the fuel tank cap is removed while applying pressure.
HINT: If the pressure does not decrease when the filler cap is removed, 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.
5. INSPECT FUEL CUTOFF VALVE AND FILL CHECK VALVE
a. Disconnect the vent line hose from the fuel tank
b. Connect the pressure gauge to the fuel tank.
c. Fill the fuel tank with fuel.
d. Apply pressure of 4 kPa (41 gf/sq.cm, 0.58 psi) to the vent port of the fuel tank.
HINT: It is necessary to 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.
e. Remove the fuel tank cap, and check that pressure drops. If the pressure does not drop, replace the fuel tank assembly.
f. 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 LEAK DETECTION PUMP (PRESSURE SENSOR)
a. Measure the power source voltage of the ECM connectors.
If the voltage is not as specified, check the ECM, leak detection pump and wire harness.
b. Measure the power output of the ECM connectors.
1. Remove the fuel tank cap.
If the voltage is not as specified, check the ECM, leak detection pump and wire harness.
2. Install the fuel tank cap.