Part 2

2GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0441: Evaporative Emission Control System Incorrect Purge Flow

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

21. INSPECT PUMP MODULE (POWER SOURCE FOR VENT VALVE)

(a) Turn the ignition switch off.
(b) Disconnect the C27 canister pump module connector.
(c) Turn the ignition switch to the ON position.
(d) Measure the voltage between terminal 9 of the canister connector and body ground.
Result:

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

(a) Turn the ignition switch off.
(b) Disconnect the C27 canister pump module connector.
(c) Apply the battery voltage to terminals 9 and 8 of the pump module.
(d) Touch the pump module to confirm the vent valve operation.
Result:

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

(a) Select the following menu items on the tester: Powertrain / Engine and ECT / Active Test / Activate the Vacuum Pump.
(b) Measure the voltage between terminal MPMP of the ECM connector and body ground when the vacuum pump is turned ON and OFF using the tester.
Result:

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

(a) Turn the ignition switch off.
(b) Disconnect the C27 canister pump module connector.
(c) Turn the ignition switch to the ON position.
(d) Select the following menu items on the tester: Powertrain / Engine and ECT / Active Test / Activate the Vacuum Pump.
(e) Turn the vacuum pump ON.
(f) Measure the voltage between terminal 1 of the canister connector and body ground.
Result:

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

(a) Disconnect the C27 canister pump module connector.
(b) Turn the ignition switch off.
(c) Check the resistance between terminal 6 of the canister connector and body ground.
Result:

(d) Reconnect the canister pump module connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- REPLACE CHARCOAL CANISTER ASSEMBLY
26. INSPECT THROTTLE BODY
(a) Stop the engine.
(b) Disconnect the EVAP hose from the throttle body.
(c) Start the engine.
(d) Confirm that the port of the throttle body has suction with your fingers.
Result:

(e) Reconnect the EVAP hose.
B -- INSPECT THROTTLE BODY
A -- REPLACE EVAP HOSE (THROTTLE BODY - PURGE VSV)
27. 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 tank cap that meets OEM specifications, and tighten it until a few click sounds are heard.

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

NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
29. LOCATE EVAP LEAK
(a) Disconnect the vent hose.

(b) Connect the EVAP pressure tester tool to the canister with the adapter.

(c) Pressurize the EVAP system by 3.2 to 3.7 kPa (24 to 28 mmHg).
(d) Apply soapy water to the piping and the connecting parts of the EVAP system.
(e) Look for areas where bubbles appear. This indicates a leak point.
(f) Repair or replace the leak point.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
30. REPLACE CHARCOAL CANISTER ASSEMBLY
(a) Replace the charcoal canister assembly Removal.
NOTE: 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; 3) the fuel tank vent hose.

NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
31. REPLACE VACUUM SWITCHING VALVE NO. 1 (PURGE VSV)

(a) Disconnect the connector and 2 hoses from the purge VSV.
(b) Remove the purge VSV.
(c) Install a new purge VSV.
(d) Reconnect the connector and 2 hoses.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
32. REPAIR OR REPLACE HARNESS OR CONNECTOR
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
33. REPLACE EVAP HOSE (THROTTLE BODY - PURGE VSV)
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
34. INSPECT THROTTLE BODY
(a) Remove the throttle body Removal.
(b) Check that the EVAP purge port of the throttle body is not clogged. If necessary, replace the throttle body.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
35. REPLACE ECM
(a) Replace the ECM Removal.
NEXT -- PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
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 -- Continue to next step.
37. PERFORM EVAPORATIVE SYSTEM CHECK (AUTO OPERATION)
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 unavailable.
- 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) On Techstream, select the following menu items: Powertrain / Engine and ECT / Utility / Evaporative System Check / Automatic Mode.
(c) After the Evaporative System Check is completed, check for pending DTCs by selecting the following menu items: Powertrain / Engine and ECT / Trouble Code / Pending.
HINT: If no pending DTC is 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*1 after the ignition switch is turned off. The purge flow monitor runs while the engine is running.
1. KEY-OFF MONITOR
5 hours*1 after the ignition switch is turned off, the electric vacuum pump creates negative pressure (vacuum) in the EVAP (Evaporative Emission) system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.
HINT: *1: 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: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.

(a) Purge VSV stuck open
In operation C, the vacuum pump creates negative pressure (vacuum) in the EVAP (Evaporative Emission) system. The EVAP system pressure is then measured by the ECM using the pressure sensor. If the stabilized system pressure is higher than [second 0.02 inch leak pressure standard x 0.2], 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).

(b) Purge VSV stuck closed
In operation D, the pressure sensor measures the EVAP (Evaporative Emission) system pressure. The pressure measurement for 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 (2.25 mmHg) 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).

2. 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 (Vacuum Switching Valve) 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 0.5 kPa (3.75 mmHg), the ECM interprets this as the purge VSV being stuck closed, and 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.

MONITOR STRATEGY