EVAP System
3UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: EVAP System
EVAP System
RELATED DTCS
If any EVAP system DTCs are set, the malfunctioning area can be determined using the table below.
NOTE:
If the 0.02 inch reference pressure difference between the first and second checks is greater than the specification, the DTCs corresponding to the reference pressure (P043E, P043F, P0441, P0455, P0456, P2401 and P2420) will all be stored.
DESCRIPTION
NOTE:
In this vehicle's EVAP system, turning ON the vent valve does not seal off the EVAP system. To check for leaks in the EVAP system, disconnect the air inlet vent hose and apply pressure from the atmosphere side of the canister.
While the engine is running, if a predetermined condition (closed loop, etc.) is met, the purge VSV is opened by the ECM and stored fuel vapors in the canister are purged to the intake manifold. The ECM changes the duty cycle ratio of the purge VSV to control purge flow volume.
The purge flow volume is also determined by the intake manifold pressure. Atmospheric pressure is allowed into the canister through the vent valve to ensure that the purge flow is maintained when the negative pressure (vacuum) is applied to the canister.
The following two monitors run to confirm appropriate EVAP system operation.
1. Key-off monitor
This monitor checks for Evaporative Emission (EVAP) system leaks and canister pump module malfunctions. The monitor starts 5 hours* after the ignition switch is turned OFF. More than 5 hours are required to allow the fuel to cool down to stabilize the Fuel Tank Pressure (FTP), thus making the EVAP system monitor more accurate.
The leak detection pump creates negative pressure (vacuum) in the EVAP system and the pressure is measured. Finally, the ECM monitors for leaks from the EVAP system and malfunctions in both the canister pump module and purge VSV based on the EVAP pressure.
HINT: *: If the engine coolant temperature is not below 35°C (95°F) 5 hours after the ignition switch is turned OFF, the monitor check starts 2 hours later. If it is still not below 35°C (95°F) 7 hours after the ignition switch is turned OFF, the monitor check starts 2.5 hours later.
2. Purge flow monitor
The purge flow monitor consists of the two monitors. The 1st monitor is conducted every time and the 2nd monitor is conducted if necessary.
- The 1st monitor
While the engine is running and the purge Vacuum Switching Valve (VSV) is ON (open), the ECM monitors the purge flow by measuring the EVAP pressure change. If negative pressure is not created, the ECM begins the 2nd monitor.
- The 2nd monitor
The vent valve is turned OFF (open) and the EVAP pressure is measured. If negative pressure is not created, the ECM interprets this as the purge VSV being stuck closed, illuminates the MIL and sets DTC P0441 (2 trip detection logic).
Atmospheric pressure check:
In order to ensure reliable malfunction detection, the variation between the atmospheric pressures, before and after conduction of the purge flow monitor, is measured by the ECM.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTE:
The Techstream is required to conduct the following diagnostic troubleshooting procedure.
HINT:
- Using the Techstream monitor results enable the EVAP system to be confirmed.
- Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. CONFIRM DTC
(a) Turn the ignition switch OFF and wait for 10 seconds.
(b) Turn the ignition switch ON.
(c) Turn the ignition switch OFF and wait for 10 seconds.
(d) Connect the Techstream to the DLC3.
(e) Turn the ignition switch ON.
(f) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(g) Confirm DTCs and freeze frame data.
If any EVAP system DTCs are set, the malfunctioning area can be determined using the table below.
NOTE:
If the 0.02 inch reference pressure difference between the first and second checks is greater than the specification, the DTCs corresponding to the reference pressure (P043E, P043F, P0441, P0455, P0456, P2401 and P2420) will all be stored.
NEXT -- Continue to next step.
2. PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
NOTICE:
- In the Evaporative System Check (Automatic Mode), the series of 5 Evaporative System Check steps are performed automatically. It takes a maximum of approximately 18 minutes.
- Do not perform the Evaporative System Check when the fuel tank is more than 90% full because the cut-off valve may be closed, making the leak check of the fuel tank not possible.
- Do not run the engine in this step.
- When the temperature of the fuel is 35°C (95°F) or more, a large amount of vapor forms and any check results become inaccurate. When performing the Evaporative System Check, keep the temperature below 35°C (95°F).
(a) Clear the DTCs DTC Check / Clear.
(b) Enter the following menus: Powertrain / Engine and ECT / Utility / Evaporative System Check / Automatic Mode.
(c) After the Evaporative System Check is completed, check for pending DTCs by entering the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
HINT: If no pending DTC is displayed, perform the Monitor Confirmation after the repair is completed. After this confirmation, check for pending DTCs. If no DTC is displayed, the EVAP system is normal.
NEXT -- Continue to next step.
3. PERFORM EVAPORATIVE SYSTEM CHECK (MANUAL MODE)
NOTICE:
- In the Evaporative System Check (Manual Mode), the series of 5 Evaporative System Check steps are performed manually.
- Do not perform the Evaporative System Check when the fuel tank is more than 90% full because the cut-off valve may be closed, making the leak check of the fuel tank not possible.
- Do not run the engine in this step.
- When the temperature of the fuel is 35°C (95°F) or more, a large amount of vapor forms and any check results become inaccurate. When performing the Evaporative System Check, keep the temperature below 35°C (95°F).
(a) Clear the DTCs DTC Check / Clear.
(b) Enter the following menus: Powertrain / Engine and ECT / Utility / Evaporative System Check / Manual Mode.
NEXT -- Continue to next step.
4. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 1/5)
(a) Check the EVAP pressure in step 1/5.
Result:
HINT: *: The DTCs related to the EVAP system are displayed on the Techstream when checking.
B -- REPLACE CANISTER ASSEMBLY
A -- Continue to next step.
5. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 1/5 TO 2/5)
(a) Check the EVAP pressure in step 1/5 and 2/5.
Result:
HINT:
- *: The DTCs related to the EVAP system are displayed on the Techstream when checking.
- The first 0.02 inch leak criterion is the value determined in step 2/5.
B -- PERFORM ACTIVE TEST USING TECHSTREAM (FOR CANISTER PUMP MODULE [LEAK DETECTION PUMP])
A -- Continue to next step.
6. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 2/5)
HINT: Make a note of the pressures checked in the steps below.
- (a) Check the EVAP pressure 4 seconds after the leak detection pump is activated*.
*: The leak detection pump begins to operate as step 1/5 proceeds to step 2/5.
- (b) Check the EVAP pressure again when it has stabilized. This pressure is the 0.02 inch leak criterion.
Result:
HINT: *: The DTCs related to the EVAP system are displayed on the Techstream when checking.
D -- PERFORM ACTIVE TEST USING TECHSTREAM (FOR VENT VALVE)
C -- REPLACE CANISTER ASSEMBLY
B -- PERFORM EVAPORATIVE SYSTEM CHECK (STEP 3/5)
A -- Continue to next step.
7. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 2/5 TO 3/5)
(a) Check the EVAP pressure in step 3/5.
Result:
HINT: *: The DTCs related to the EVAP system are displayed on the Techstream when checking.
C -- REPLACE CANISTER ASSEMBLY
B -- PERFORM ACTIVE TEST USING TECHSTREAM (FOR VENT VALVE)
A -- Continue to next step.
8. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 3/5)
(a) Wait until the EVAP pressure change is less than 0.1 kPa (0.75 mmHg) for 30 seconds.
(b) Measure the EVAP pressure and record it.
HINT: A few minutes are required for the EVAP pressure to become saturated. When there is little fuel in the fuel tank, it takes up to 900 seconds (15 minutes).
NEXT -- Continue to next step.
9. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 4/5)
(a) Check the EVAP pressure in step 4/5.
Result:
HINT: *: The DTCs related to the EVAP system are displayed on the Techstream when checking.
C -- PERFORM ACTIVE TEST USING TECHSTREAM (PURGE VSV)
B -- CHECK PURGE LINE HOSE (PURGE VSV - INTAKE MANIFOLD)
A -- Continue to next step.
10. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 5/5)
(a) Check the EVAP pressure in step 5/5.
(b) Compare the EVAP pressure in step 3/5 and the second 0.02 inch leak criterion (step 5/5).
Result:
HINT: *: The DTCs related to the EVAP system are displayed on the Techstream when checking.
B -- PERFORM ACTIVE TEST USING TECHSTREAM (PURGE VSV)
A -- REPAIR OR REPLACE PARTS AND COMPONENTS INDICATED BY OUTPUT DTCS
11. PERFORM EVAPORATIVE SYSTEM CHECK (STEP 3/5)
(a) Check the EVAP pressure in step 3/5.
Result:
HINT:
- *: The DTCs related to the EVAP system are displayed on the Techstream when checking.
- The first 0.02 inch leak criterion is the value determined in step 2/5.
B -- PERFORM ACTIVE TEST USING TECHSTREAM (FOR CANISTER PUMP MODULE [LEAK DETECTION PUMP])
A -- REPLACE CANISTER ASSEMBLY
12. PERFORM ACTIVE TEST USING TECHSTREAM (PURGE VSV)
(a) Enter the following menus: Powertrain / Engine / Active Test / Activate the VSV for EVAP Control.
(b) Disconnect the hose (connected to the canister) from the purge VSV.
(c) Start the engine.
(d) Using the tester, turn the purge VSV OFF.
(e) Use your finger to confirm that the purge VSV has no suction.
(f) Using the tester, turn the purge VSV ON.
(g) Use your finger to confirm that the purge VSV has suction.
Result:
C -- CHECK PURGE LINE HOSE (PURGE VSV - INTAKE MANIFOLD)
B -- INSPECT PURGE VSV
A -- Continue to next step.
13. CHECK FUEL TANK CAP
(a) Check that the fuel tank cap is correctly installed and confirm the fuel cap meets OEM specification.
(1) Tighten the fuel tank cap until a few click sounds are heard.
HINT: If an EVAP tester is available, use the tester to check the fuel tank cap.
(b) Remove the fuel tank cap and install it onto the fuel tank cap adaptor.
(c) Connect an EVAP tester pump hose to the adaptor, and pressurize the cap to 3.2 to 3.7 kPa (24 to 28 mmHg) using an EVAP tester pump.
(d) Seal the adaptor and wait for 2 minutes.
(e) Check the pressure. If the pressure is 2 kPa (15 mmHg) or more, the fuel tank cap is normal.
Result:
C -- REPLACE FUEL TANK CAP
B -- CORRECTLY REINSTALL OR REPLACE FUEL TANK CAP
A -- LOCATE EVAP LEAK
14. INSPECT PURGE VSV
(a) Turn the ignition switch OFF.
(b) Disconnect the V4 purge VSV connector.
(c) Disconnect the purge line hose (connected to the canister) from the purge VSV.
(d) Start the engine.
(e) Use your finger to confirm that the purge VSV has no suction.
Result:
B -- REPLACE PURGE VSV
A -- REPLACE ECM
15. CHECK PURGE LINE HOSE (PURGE VSV - INTAKE MANIFOLD)
(a) Disconnect the purge line hose (connected to the intake manifold) from the purge VSV.
(b) Start the engine.
(c) Use your finger to confirm that the hose has suction.
Result:
B -- INSPECT INTAKE MANIFOLD (EVAP PURGE PORT)
A -- Continue to next step.
16. INSPECT PURGE VSV
(a) Disconnect the V4 purge VSV connector.
(b) Apply battery voltage to the terminals of the purge VSV.
(c) Using an air gun, confirm that air flows from port A to port B.
Result:
B -- REPLACE PURGE VSV
A -- Continue to next step.
17. CHECK WIRE HARNESS (POWER SOURCE OF PURGE VSV)
(a) Disconnect the V4 purge VSV connector.
(b) Turn the ignition switch ON.
(c) Measure the voltage of the wire harness side connector.
Result:
B -- REPAIR OR REPLACE HARNESS AND CONNECTOR
A -- Continue to next step.
18. CHECK WIRE HARNESS (PURGE VSV - ECM)
(a) Disconnect the V4 purge VSV connector.
(b) Disconnect the E2 ECM connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- REPLACE ECM
19. PERFORM ACTIVE TEST USING TECHSTREAM (FOR VENT VALVE)
(a) Turn the ignition switch ON.
(b) Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the VSV for Vent Valve.
(c) Measure the voltage between terminal VPMP of the ECM connector and the body ground when the vent valve is turned ON (closed) and OFF (vent) using the tester.
Result:
C -- REPLACE ECM
B -- INSPECT CANISTER PUMP MODULE (VENT VALVE OPERATION)
A -- Continue to next step.
20. INSPECT CANISTER PUMP MODULE (POWER SOURCE FOR VENT VALVE)
(a) Turn the ignition switch OFF.
(b) Disconnect the C12 canister pump module connector.
(c) Turn the ignition switch ON.
(d) Measure the voltage of the wire harness side connector.
Result:
B -- REPAIR OR REPLACE HARNESS AND CONNECTOR
A -- Continue to next step.
21. INSPECT CANISTER PUMP MODULE (VENT VALVE OPERATION)
(a) Turn the ignition switch OFF.
(b) Disconnect the C12 canister pump module connector.
(c) Apply the battery voltage to terminals 9 and 8 of the canister pump module.
(d) Touch the canister pump module to confirm the vent valve operation.
Result:
B -- REPLACE CANISTER ASSEMBLY
A -- REPAIR OR REPLACE HARNESS AND CONNECTOR
22. PERFORM ACTIVE TEST USING TECHSTREAM (FOR CANISTER PUMP MODULE [LEAK DETECTION PUMP])
(a) Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the Vacuum Pump.
(b) Measure the voltage between MPMP terminal of the ECM connector and the body ground when the leak detection pump is turned ON and OFF using the tester.
Result:
B -- REPLACE ECM
A -- Continue to next step.
23. CHECK WIRE HARNESS (CANISTER PUMP MODULE - ECM)
(a) Turn the ignition switch OFF.
(b) Disconnect the C12 canister pump module connector.
(c) Turn the ignition switch ON.
(d) Enter the following menus: Powertrain / Engine and ECT / Active Test / Activate the Vacuum Pump.
(e) Turn the leak detection pump ON.
(f) Measure the voltage of the wire harness side connector.
Result:
B -- REPAIR OR REPLACE HARNESS AND CONNECTOR
A -- Continue to next step.
24. CHECK WIRE HARNESS (CANISTER PUMP MODULE - GROUND)
(a) Disconnect the C12 canister pump module canister connector.
(b) Turn the ignition switch OFF.
(c) Measure the resistance of the wire harness side connectors between terminal 6 of the C12 connector and the body ground.
Result:
B -- REPAIR OR REPLACE HARNESS AND CONNECTOR
A -- REPLACE CANISTER ASSEMBLY
25. INSPECT INTAKE MANIFOLD (EVAP PURGE PORT)
(a) Turn the ignition switch OFF.
(b) Disconnect the purge line hose from the intake manifold.
(c) Turn the ignition switch ON.
(d) Use your finger to confirm that the port of the intake manifold has suction.
Result:
B -- INSPECT INTAKE MANIFOLD (EVAP PURGE PORT)
A -- REPLACE PURGE LINE HOSE (INTAKE MANIFOLD - PURGE VSV)
26. CORRECTLY REINSTALL OR REPLACE FUEL TANK CAP
HINT:
- When reinstalling the fuel tank cap, tighten it until a few click sounds are heard.
- When replacing the fuel tank cap, use a fuel cap that meets OEM specifications, and tighten it until a few click sounds are heard.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
27. REPLACE FUEL TANK CAP
HINT: When installing the fuel tank cap, tighten it until a few click sounds are heard.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
28. LOCATE EVAP LEAK
(a) Disconnect the vent hose.
(b) Install the EVAP pressure tester tool to the vent hose with the adapter.
(c) Pressurize the EVAP system to 3.2 to 3.7 kPa (24 to 28 mmHg).
(d) Apply soapy water to the piping and connecting parts of the EVAP system.
(e) Look for areas where bubbles appear. This indicates leak point.
(f) Repair or replace the leak point.
HINT: Disconnect the hose between the canister and the fuel tank from the canister. Block the canister side and conduct an inspection. In this way, the fuel tank can be excluded as an area suspected of causing fuel leaks.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
29. REPLACE CANISTER ASSEMBLY
(a) Replace the canister assembly Removal.
NOTE:
When replacing the canister, check the canister pump module interior and related pipes for water, fuel or other liquids. If liquids are present, check for disconnections and/or cracks in the following: 1) the pipe from the air inlet port to the canister pump module; 2) the canister filter; and 3) the fuel tank vent hose.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
30. REPLACE PURGE VSV
(a) Disconnect the connector and hoses from the purge VSV.
(b) Remove the purge VSV.
(c) Install a new purge VSV.
(d) Reconnect the connector and hose.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
31. REPAIR OR REPLACE HARNESS AND CONNECTOR
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
32. REPLACE PURGE LINE HOSE (INTAKE MANIFOLD - PURGE VSV)
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
33. INSPECT INTAKE MANIFOLD (EVAP PURGE PORT)
(a) Check that the EVAP purge port of the intake manifold is not clogged. If necessary, replace the intake manifold.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
34. REPLACE ECM
(a) Replace the ECM.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
35. REPAIR OR REPLACE PARTS AND COMPONENTS INDICATED BY OUTPUT DTCS
(a) Repair the malfunctioning areas indicated by the DTCs that had been confirmed when the vehicle was brought in.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
36. PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
NOTICE:
- In the Evaporative System Check (Automatic Mode), the series of 5 Evaporative System Check steps are performed automatically. It takes a maximum of approximately 18 minutes.
- Do not perform the Evaporative System Check when the fuel tank is more than 90% full because the cut-off valve may be closed, making the leak check of the fuel tank not possible.
- Do not run the engine in this step.
- When the temperature of the fuel is 35°C (95°F) or more, a large amount of vapor forms and any check results become inaccurate. When performing an Evaporative System Check, keep the temperature below 35°C (95°F).
(a) Clear the DTCs DTC Check / Clear.
(b) Enter the following menus: Powertrain / Engine and ECT / Utility / Evaporative System Check / Automatic Mode.
(c) After the Evaporative System Check is completed, check for pending DTCs by entering the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
HINT: If no pending DTC is found, the repair has been successfully completed.
NEXT -- COMPLETED
CONFIRMATION DRIVING PATTERN
HINT: After a repair, check Monitor Status by performing the key-off monitor confirmation and purge flow monitor confirmation described below.
1. Key-off monitor confirmation
(a) Preconditions
The monitor will not run unless:
- The vehicle has been driven for 10 minutes or more (in a city area or on a freeway)
- The fuel tank is less than 90% full
- The altitude is less than 8000 ft. (2400 m)
- The Engine Coolant Temperature (ECT) is between 4.4 to 35°C (40 to 95°F)
- The Intake Air Temperature (IAT) is between 4.4 to 35°C (40 to 95°F)
- The vehicle remains stationary (the vehicle speed is 0 km/h (0 mph))
(b) Monitor Conditions
1 Allow the engine to idle for at least 5 minutes.
2 Turn the ignition switch OFF and wait for 10 hours.
HINT: Do not start the engine until checking Monitor Status. If the engine is started, the steps described above must be repeated.
(c) Monitor Status
1 Connect the Techstream to the DLC3.
2 Turn the ignition switch ON.
3 Enter the following menus: Powertrain / Engine and ECT / Monitor / Evaporative System.
4 Check the Monitor Status displayed on the tester.
HINT: If Incomplete is displayed, the monitor is not completed. Make sure that the preconditions have been met, and perform the Monitor Conditions again.
2. Purge flow monitor confirmation (P0441)
HINT: Perform this monitor confirmation after the key-off monitor confirmation shows Complete.
(a) Preconditions
The monitor will not run unless:
- The vehicle has been driven for 10 minutes or more (in a city area or on a freeway)
- The ECT is between 4.4 to 35°C (40 to 95°F)
- The IAT is between 4.4 to 35°C (40 to 95°F)
(b) Monitor Conditions
1 Release the pressure from the fuel tank by removing and reinstalling the fuel cap.
2 Warm the engine up until the ECT reaches more than 75°C (167°F).
3 Increase the engine speed to 3000 rpm once.
4 Allow the engine to idle and turn the A/C ON for 1 minute.
(c) Monitor Status
1 Turn the ignition switch OFF (when ON or the engine is running).
2 Connect the Techstream to the DLC3.
3 Turn the ignition switch ON.
4 Enter the following menus: Powertrain / Engine and ECT / Utility.
5 Check the Monitor Status displayed on the tester.
HINT: If INCMP is displayed, the monitor is not completed. Make sure that the preconditions have been met, and perform the "Monitor Conditions" procedures again.
MONITOR RESULT
Refer to CHECKING MONITOR STATUS Mode 6 Data.
