Part 2

2UR-GSE ENGINE CONTROL: SFI SYSTEM: P0441: Evaporative Emission Control System Incorrect Purge Flow

DTC P0441 - Evaporative Emission Control System Incorrect Purge Flow - Continued

15. CHECK EVAP HOSE (PURGE VSV - INTAKE MANIFOLD)
(a) Turn the engine switch off.

(b) Disconnect the hose (connected to the intake manifold) from the purge VSV.
(c) Start the engine.
(d) Use your finger to confirm that the hose has suction.
Result:

(e) Reconnect the hose.
B -- INSPECT INTAKE MANIFOLD (EVAP PURGE PORT)
A -- Continue to next step.
16. INSPECT PURGE VSV

(a) Remove the purge VSV.
(b) Apply the 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 (PURGE VSV)
A -- Continue to next step.
17. CHECK HARNESS AND CONNECTOR (POWER SOURCE OF PURGE VSV)

(a) Disconnect the purge VSV connector.
(b) Turn the engine switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Result:

(d) Reconnect the purge VSV connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.
18. CHECK HARNESS AND CONNECTOR (PURGE VSV - ECM)

(a) Disconnect the purge VSV connector.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):

Standard Resistance (Check for Short):

(d) Reconnect the VSV connector and ECM connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM
19. PERFORM ACTIVE TEST USING TECHSTREAM (FOR VENT VALVE)

(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Enter the following menus: Powertrain / Active Test / Activate the VSV for Vent Valve.
(d) Measure the voltage according to the value(s) in the table below.
Result:

B -- REPLACE ECM
A -- INSPECT CANISTER PUMP MODULE (VENT VALVE OPERATION)
20. PERFORM ACTIVE TEST USING TECHSTREAM (FOR VENT VALVE)

C -- REPLACE ECM
B -- INSPECT CANISTER PUMP MODULE (VENT VALVE OPERATION)
A -- Continue to next step.
21. INSPECT CANISTER PUMP MODULE (POWER SOURCE FOR VENT VALVE)

(a) Turn the engine switch off.
(b) Disconnect the canister pump module connector.
(c) Turn the engine switch on (IG).
(d) Measure the voltage according to the value(s) in the table below.
Result:

(e) Reconnect the canister pump module connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.
22. INSPECT CANISTER PUMP MODULE (VENT VALVE OPERATION)

(a) Turn the engine switch off.
(b) Disconnect the canister pump module connector.
(c) Apply the battery voltage to VLVB and VGND terminals of the canister pump module.
(d) Touch the canister pump module to confirm the vent valve operation.
Result:

(e) Reconnect the canister pump module connector.
B -- REPLACE CANISTER ASSEMBLY
A -- REPAIR OR REPLACE HARNESS OR CONNECTOR
23. PERFORM ACTIVE TEST USING TECHSTREAM (FOR LEAK DETECTION PUMP)

(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Enter the following menus: Powertrain / Active Test / Activate the Vacuum Pump.
(d) Measure the voltage according to the value(s) in the table below.
Result:

B -- REPLACE ECM
A -- Continue to next step.
24. CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - ECM)

(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch off.
(c) Disconnect the canister pump module connector.
(d) Turn the engine switch on (IG) and turn the Techstream ON.
(e) Enter the following menus: Powertrain / Active Test / Activate the Vacuum Pump.
(f) Turn the leak detection pump (vacuum pump) ON.
(g) Measure the voltage according to the value(s) in the table below.
Result:

(h) Reconnect the canister pump module connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.
25. CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - GROUND)

(a) Turn the engine switch off.
(b) Disconnect the canister pump module connector.
(c) Measure the resistance according to the value(s) in the table below.
Result:

(d) Reconnect the canister pump module connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- REPLACE CANISTER ASSEMBLY
26. INSPECT INTAKE MANIFOLD (EVAP PURGE PORT)
(a) Stop the engine.
(b) Disconnect the EVAP hose from the intake air surge tank.
(c) Start the engine.
(d) Use your finger to confirm that the port of the intake air surge tank has suction.
Result:

(e) Reconnect the EVAP hose.
B -- INSPECT INTAKE MANIFOLD
A -- REPLACE EVAP HOSE (INTAKE AIR SURGE TANK - PURGE VSV)
27. CORRECTLY REINSTALL OR REPLACE FUEL CAP ASSEMBLY
HINT:
- When reinstalling the fuel cap, tighten it until a few click sounds are heard.
- When replacing the fuel cap, use a fuel cap that meets OEM specifications, and install it until a few click sounds are heard.

NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
28. REPLACE FUEL CAP ASSEMBLY
HINT: When installing the fuel cap, tighten it until a few click sounds are heard.

NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
29. LOCATE EVAP LEAK PART
(a) Disconnect the pressure gauge to the canister with the adapter.

(b) Connect the EVAP pressure tester tool to the canister 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 the 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.
(g) Reconnect the vent hose.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
30. REPLACE CANISTER ASSEMBLY
(a) Replace the canister assembly Removal.

NOTICE:
When replacing the canister, check the canister pump module interior and related pipes for water, fuel and 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)
31. REPLACE PURGE VSV (PURGE VSV)
(a) Replace the purge VSV Removal.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
32. REPAIR OR REPLACE HARNESS OR CONNECTOR
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
33. REPLACE EVAP HOSE (INTAKE AIR SURGE TANK - PURGE VSV)
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
34. INSPECT INTAKE MANIFOLD
(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)
35. REPLACE ECM
(a) Replace the ECM Removal.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
36. 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)
37. PERFORM EVAPORATIVE SYSTEM CHECK (AUTOMATIC MODE)
NOTICE:
- The Evaporative System Check (Automatic Mode) consists of five steps performed automatically by the Techstream. 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 fuel tank leak check unavailable.
- Do not run the engine during this operation.
- 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 DTCs DTC Check / Clear.
(b) Enter the following menus: Powertrain / Engine / 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 / Trouble Codes.
HINT: If no pending DTCs are found, the repair has been successfully completed.

NEXT -- COMPLETED

MONITOR DESCRIPTION

The two monitors, key-off and purge flow, are used to detect malfunctions relating to DTC P0441. The key-off monitor is initiated by the ECM internal timer, known as the soak timer, 5 hours* after the engine switch is turned off. The purge flow monitor runs while the engine is running.

- KEY-OFF MONITOR
5 hours* after the engine switch is turned off, the leak detection pump creates negative pressure (vacuum) in the EVAP system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.
HINT: *: If the engine coolant temperature is not below 35°C (95°F) 5 hours after the engine 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 engine switch is turned off, the monitor check starts 2.5 hours later.

*: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.

1. Purge VSV stuck open
In operation C, the leak detection pump creates negative pressure (vacuum) in the EVAP system. The EVAP system pressure is then measured by the ECM using the canister pressure sensor. If the stabilized system pressure is higher than [second reference pressure x 0.32], the ECM interprets this as the purge VSV (Vacuum Switching Valve) being stuck open. The ECM illuminates the MIL and sets the DTC (2 trip detection logic).

2. Purge VSV stuck closed
In operation D, the canister pressure sensor measures the EVAP system pressure. The pressure measurement for the purge VSV monitor is begun when the purge VSV is turned ON (open) after the EVAP leak check. When the measured pressure indicates an increase of 0.3 kPa-g (2.25 mmHg-g) or more, the purge VSV is functioning normally. If the pressure does not increase, the ECM interprets this as the purge VSV being stuck closed. The ECM illuminates the MIL and sets the DTC (2 trip detection logic).

- PURGE FLOW MONITOR

The purge flow monitor consists of the two step monitors. The 1st monitor is conducted every time and the 2nd monitor is activated if necessary.

- The 1st monitor
While the engine is running and the purge 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 ON (closed) and the EVAP pressure is then measured. If the variation in the pressure is less than 0.3 kPa-g (2.25 mmHg-g), 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.

OBD II MONITOR SPECIFICATIONS

1. Key-off Monitor

Monitor Strategy