Part 2

1AR-FE ENGINE CONTROL: SFI SYSTEM: P0441: Evaporative Emission Control System Incorrect Purge Flow

DTC P0441 - Evaporative Emission Control System Incorrect Purge Flow

(CONTINUED)

13. CHECK FUEL CAP
(a) Check that the fuel cap is correctly installed and confirm that the fuel cap meets OEM specifications.
(b) Tighten the fuel cap until a few click sounds are heard.
HINT: If an EVAP tester is available, check the fuel cap using the Techstream.

1. Remove the fuel cap and install it onto a fuel cap adapter.
2. Connect an EVAP tester pump hose to the adapter, and pressurize the cap to 3.2 to 3.7 kPa-g (24 to 28 mmHg-g) using an EVAP tester pump.
3. Seal the adapter and wait for 2 minutes.
4. Check the pressure. If the pressure is 2 kPa-g (15 mmHg-g) or more, the fuel cap is normal.

Result:

(c) Reinstall the fuel cap.
C -- REPLACE FUEL CAP
B -- CORRECTLY REINSTALL OR REPLACE FUEL CAP
A -- LOCATE EVAP LEAK PART

14. INSPECT PURGE VSV

(a) Turn the ignition switch off.
(b) Disconnect the purge VSV connector.

Text in Illustration

(c) Disconnect the 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:

(f) Reconnect the purge VSV connector.
(g) Reconnect the hose.
B -- REPLACE PURGE VSV
A -- REPLACE ECM
15. CHECK EVAP HOSE (PURGE VSV - INTAKE MANIFOLD ASSEMBLY)

(a) Disconnect the hose (connected to the intake manifold assembly) from the purge VSV.

Text in Illustration

(b) Start the engine.
(c) Use your finger to confirm that the hose has suction.
Result:

(d) Reconnect the hose.
B -- INSPECT INTAKE MANIFOLD ASSEMBLY (EVAP PURGE PORT)
A -- Continue to next step.

16. INSPECT PURGE VSV

(a) Remove the purge VSV.
(b) Apply battery voltage to the terminals of the purge VSV.

Text in Illustration

(d) Install the purge VSV.
B -- REPLACE 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 ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Result:

Text in Illustration

(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 ECM connector.

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

Standard Resistance (Check for Short):

Text in Illustration

(d) Reconnect the purge VSV connector.
(e) Reconnect the ECM connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM
19. INSPECT CANISTER PUMP MODULE (POWER SOURCE FOR VENT VALVE)
(a) Disconnect the canister pump module connector.

(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Result:

Text in Illustration

(d) Reconnect the canister pump module connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.

20. INSPECT CANISTER PUMP MODULE (VENT VALVE OPERATION)

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

Text in Illustration

(d) Reconnect the canister pump module connector.
B -- REPLACE CHARCOAL CANISTER ASSEMBLY
A -- Continue to next step.

21. CHECK HARNESS AND CONNECTOR (ECM - CANISTER PUMP MODULE)
(a) Disconnect the ECM connector.

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

Text in Illustration

(d) Reconnect the ECM connector.
(e) Reconnect the canister pump module connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- REPLACE ECM
22. PERFORM ACTIVE TEST USING TECHSTREAM (ACTIVE THE VACUUM PUMP)
(a) Turn the ignition switch off.

(b) Disconnect the canister pump module connector.
(c) Turn the ignition switch to ON.
(d) Enter the following menus: Powertrain / Engine / Active Test / Activate the Vacuum Pump.
(e) Measure the voltage according to the value(s) in the table below.
Result:

Text in Illustration

(f) Reconnect the canister pump module connector.
C -- REPLACE ECM
B -- CHECK HARNESS AND CONNECTOR (ECM - CANISTER PUMP MODULE)
A -- Continue to next step.

23. CHECK HARNESS AND CONNECTOR (CANISTER PUMP MODULE - BODY GROUND)
(a) Disconnect the canister pump module connector.

(b) Measure the resistance according to the value(s) in the table below.
Result:

Text in Illustration

(c) Reconnect the canister pump module connector.
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- REPLACE CHARCOAL CANISTER ASSEMBLY
24. CHECK HARNESS AND CONNECTOR (ECM - CANISTER PUMP MODULE)
(a) Disconnect the canister pump module connector.

(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Result:

Text in Illustration

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

(d) Reconnect the EVAP hose.
B -- INSPECT INTAKE MANIFOLD ASSEMBLY (EVAP PURGE PORT)
A -- REPLACE EVAP HOSE (INTAKE MANIFOLD ASSEMBLY - PURGE VSV)
26. CORRECTLY REINSTALL OR REPLACE FUEL CAP
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 EVAP SYSTEM CHECK (AUTOMATIC MODE)
27. REPLACE FUEL CAP
HINT: When installing the fuel cap, tighten it until a few click sounds are heard.

NEXT -- PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
28. LOCATE EVAP LEAK PART
(a) Disconnect the vent hose.

Text in Illustration

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

Text in Illustration

(c) Pressurize the EVAP system to 3.2 to 3.7 kPa-g (24 to 28 mmHg-g).
(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 fuel tank from the canister. Block the charcoal canister assembly side and conduct an inspection. In this way, the fuel tank can be excluded as an area suspected of causing fuel leaks.

NEXT -- PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
29. REPLACE CHARCOAL 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 air filter; and 3) the fuel tank vent hose.

Text in Illustration

NEXT -- PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
30. REPLACE PURGE VSV

(a) Disconnect the connector and the 2 hoses from the purge VSV.

Text in Illustration

(b) Remove the purge VSV.
(c) Install a new purge VSV.
(d) Reconnect the connector and 2 hoses.
NEXT -- PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
31. REPAIR OR REPLACE HARNESS OR CONNECTOR
NEXT -- PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
32. REPLACE EVAP HOSE (INTAKE MANIFOLD ASSEMBLY - PURGE VSV)
NEXT -- PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
33. INSPECT INTAKE MANIFOLD ASSEMBLY (EVAP PURGE PORT)
(a) Check that the EVAP purge port of the intake manifold assembly is not clogged. If necessary, replace the intake manifold assembly.
NEXT -- PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
34. REPLACE ECM
(a) Replace the ECM Removal.
NEXT -- PERFORM EVAP 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 -- Continue to next step.

36. PERFORM EVAP SYSTEM CHECK (AUTOMATIC MODE)
NOTICE:
- The Evaporative System Check (Automatic Mode) consists of 5 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 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 fuel temperature below 35°C (95°F).
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear the DTCs DTC Check / Clear.
(e) Enter the following menus: Powertrain / Engine / Utility / Evaporative System Check / Automatic Mode.
(f) 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 2 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 ignition switch is turned off. The purge flow monitor runs while the engine is running.
1. KEY-OFF MONITOR
5 hours* after the ignition 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 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.

*: 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 0.22], the ECM interprets this as the purge VSV (Vacuum Switching Valve) being stuck open. The ECM illuminates the MIL and stores 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 begins 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 stores the DTC (2 trip detection logic).

2. PURGE FLOW MONITOR

The purge flow monitor consists of two 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 0.4 kPa-g (3.0 mmHg-g), the ECM interprets this as the purge VSV being stuck closed, illuminates the MIL and stores 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

TYPICAL ENABLING CONDITIONS

All

Key-off Monitor

Purge Flow Monitor

TYPICAL MALFUNCTION THRESHOLDS

Purge VSV Stuck Open

Purge VSV Stuck Closed

Purge Flow

MONITOR RESULT

Refer to Checking Monitor Status Mode 6 Data.

CONFIRMATION DRIVING PATTERN

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
4. Turn the ignition switch off.
5. Turn the ignition switch to ON and turn the Techstream on [A].
6. Start the engine and wait 15 minutes or more [B].
7. Enter the following menus: Powertrain / Engine / Utility / All readiness.
8. Input the DTC: P0441.
9. Check the DTC judgment result [C].

NOTICE:
- The Evaporative System Check (Automatic Mode) consists of 5 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 higher, a large amount of vapor forms and any check results become inaccurate. When performing the Evaporative System Check, keep the fuel temperature below 35°C (95°F).

10. Turn the ignition switch to ON and turn the Techstream on.
11. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
12. Turn the ignition switch off.
13. Turn the ignition switch to ON and turn the Techstream on.
14. Enter the following menus: Powertrain / Engine / Utility / Evaporative System Check / Automatic Mode [D].
15. After the "Evaporative System Check" is completed, check for All Readiness by entering the following menus: Powertrain / Engine / Utility / All Readiness.
16. Input the DTC: P0441.
17. Check the DTC judgment result [E].

HINT: If the judgment result shows ABNORMAL, the system has a malfunction.

18. If the test result is UNKNOWN, enter the following menus: Powertrain / Engine / Trouble Codes / Pending.
19. Read Pending DTCs.
HINT: If a pending DTC is output, the system is malfunctioning.

20 If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.
HINT:
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.