Brand:

Toyota

Model Name:

4Runner GRN210 215 UZN210 215

Manual:

Repair Manual

Section:

1Gr-Fe Engine Control System

Title:

Sfi System

  1. Dtc summary

  2. Description

  3. Inspection procedure

  4. Monitor description

  5. Monitor strategy

  6. Typical enabling conditions

  7. Typical malfunction thresholds

  8. Monitor result

DTC P0441 Evaporative Emission Control System Incorrect Purge Flow


​

DTC SUMMARY


DTCs
Monitoring Items
Malfunction Detection Conditions
Trouble Areas
Detection Timings
Detection Logic
P0441
Purge VSV (Vacuum Switching Valve) stuck open
Vacuum pump creates negative pressure (vacuum) in EVAP system and EVAP system pressure is measured. The 0.02 inch leak pressure standard is measured at the start and end of the leak check.
If stabilized pressure is higher than [second 0.02 inch leak pressure standard x 0.2], ECM determines that purge VSV is stuck open
  1. Purge VSV
  2. Connector/wire harness
    (Purge VSV - ECM)
  3. ECM
  4. Pump module
  5. Leakage from EVAP system
While ignition Switch OFF
2 trip
P0441
Purge VSV stuck closed
After EVAP leak check performed, purge VSV turned ON (open), and atmospheric air is introduced into EVAP system. 0.02 inch leak pressure standard is measured at the start and end of leak check.
If pressure does not return to near atmospheric pressure, ECM determines that purge valve is stuck closed
  1. Purge VSV
  2. Connector/wire harness
    (Purge VSV - ECM)
  3. ECM
  4. Pump module
  5. Leakage from EVAP system
While ignition Switch OFF
2 trip
P0441
Purge flow
While engine running, the following conditions successively met:
  1. Negative pressure is not created in EVAP system when purge VSV is turned ON (open)
  2. EVAP system pressure change is less than 0.5 kPa (3.75 mmHg) when vent valve is turned ON (closed)
  3. Atmospheric pressure change before and after purge flow monitor is less than 0.1 kPa (0.75 mmHg)
  1. Purge VSV
  2. Connector/wire harness
    (Purge VSV - ECM)
  3. Leakage from EVAP line
    (Purge VSV - Intake manifold)
  4. ECM
While engine running
2 trip

DESCRIPTION

The circuit description can be found in the EVAP (Evaporative Emission) System (Click here).

INSPECTION PROCEDURE

Refer to the EVAP System (Click here).

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 to off. The purge flow monitor runs while the engine is running.

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.

Sequence
Operations
Descriptions
Duration
-
ECM activation
Activated by soak timer, 5 hours (7 or 9.5 hours) after ignition switch turned off.
-
A
Atmospheric pressure measurement
Vent valve turned OFF (vent) and EVAP system pressure measured by ECM in order to register atmospheric pressure.
If pressure in EVAP system is not between 70 kPa and 110 kPa (525 mmHg and 825 mmHg), ECM cancels EVAP system monitor.
10 seconds
B
First 0.02 inch leak pressure measurement
In order to determine 0.02 inch leak pressure standard, vacuum pump creates negative pressure (vacuum) through 0.02 inch orifice and then ECM checks if vacuum pump and vent valve operate normally.
60 seconds
C
EVAP system pressure measurement
Vent valve turned ON (closed) to shut EVAP system.
Negative pressure (vacuum) is created in EVAP system, and EVAP system pressure then measured.
Write down measured value as it will be used in the leak check.
If EVAP pressure does not stabilize within 15 minutes, ECM cancels EVAP system monitor.
15 minutes*2
D
Purge VSV monitor
Purge VSV is opened and then EVAP system pressure is measured by ECM.
Large increase indicates normal.
10 seconds
E
Second 0.02 inch leak pressure measurement
After second 0.02 inch leak pressure measurement, leak check is performed by comparing first and second 0.02 inch leak pressure standards.
If stabilized system pressure is higher than second 0.02 inch leak pressure standard, ECM determines that EVAP system leaking.
60 seconds
F
Final check
Atmospheric pressure is measured and then monitoring result is recorded by ECM.
-
*2: If only a small amount of fuel in the fuel tank, it takes longer for the EVAP pressure to stabilize.

Purge VSV stuck openIn 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). 4Runner

  1. 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).


    Purge VSV stuck closedIn 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). 4Runner

  2. 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).


    The 1st monitorWhile 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. 4Runner


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.
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.
The 1st monitorWhile 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. 4Runner
  1. 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.
  2. 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).

MONITOR STRATEGY


Related DTCs
P0441: Purge VSV stuck open
P0441: Purge VSV stuck closed
P0441: Purge flow
Required Sensors / Components
Purge VSV and pump module
Frequency of Operation
Once per driving cycle
Duration
Purge VSV stuck open and closed: Within 15 minutes. (varies with amount of fuel in tank)
Purge flow: Within 10 minutes
MIL Operation
2 driving cycles
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


All:
The monitor is run whenever this DTC is not present
P0011, P0012 (VVT System-Advance, Retard), P0021, P0022 (VVT System2-Adavance, Retard), P0100, P0101, P0102, P0103 (MAF Sensor), P0110, P0112, P0113 (IAT Sensor),P0115, P0116, P0117, P0118 (ECT Sensor), P0120, P0121, P0122, P0123, P0220, P0222, P0223 , P2135 (TP Sensor), P0125 (Insufficient ECT for Closed Loop), P0171,P0172 (Fuel System), P0300, P0301, P0302, P0303, P0304, P0305, P0306 (Misfire), P0335 (CKP Sensor), P0340 (CMP sensor), P0342, P0343, P0345 (VVT Sensor 1, 2), P0351, P0352, P0353, P0354, P0355, P0356 (Ignitor), P0450, P0451, P0452, P0453 (EVAP pressure Sensor), P0500 (VSS)

Purge VSV stuck open and closed:
Atmospheric pressure
70 to 110 kPa (525 to 825 mmHg)
Battery voltage
10.5 V or more
Vehicle speed
Less than 2.5 mph (4 km/h)
Ignition switch
OFF
Time after key-off
5 or 7 or 9.5 hours
EVAP pressure sensor malfunction (P0450, P0452, P0453)
Not detected
EVAP canister purge valve
Not operated by scan tool
EVAP canister vent valve
Not operated by scan tool
EVAP leak detection pump
Not operated by scan tool
Both of the following conditions are met before key off
Condition 1 and 2
1. Duration that vehicle has been driven
5 minutes or more
2. EVAP purge operation
Performed
ECT
4.4 to 35°C (40 to 95°F)
IAT
4.4 to 35°C (40 to 95°F)
Key-off monitor sequence 1 to 8

  1. 1. Atmospheric pressure measurement
    Next sequence is run if the following condition is set
    		-
    Atmospheric pressure change
    		Less than 0.3 kPa (2.25 mmHg) in 1 second

    2. First reference pressure measurement
    Next sequence is run if the following conditions are set
    		Condition 1, 2 and 3
    1. EVAP pressure just after reference pressure measurement start
    		-1 kPa (-7.5 mmHg) or less
    2. Reference pressure
    		-4.85 to -1.057 kPa (-36.38 to -7.93 mmHg)
    3. Reference pressure
    		Saturated

    3. EVAP canister vent valve close stuck check
    Next sequence is run if the following condition is set
    		-
    EVAP pressure change after vent valve is ON
    		0.3 kPa (2.25 mmHg) or more

    4. Vacuum introduction
    Next sequence is run if the following condition is set
    		-
    EVAP pressure
    		Saturated within 12 minutes

    5. EVAP canister purge valve close stuck check
    Next sequence is run if the following condition is met
    		-
    EVAP pressure change after purge valve is open
    		0.3 kPa (2.25 mmHg) or more

    6. Second reference pressure measurement
    Next sequence is run if the following conditions are met
    		Condition 1, 2, 3 and 4
    1. EVAP pressure just after reference pressure
    		-1 kPa (-7.5 mmHg) or less
    2. Reference pressure
    		-4.85 to -1.057 kPa (-36.384 to -7.929 mmHg)
    3. Reference pressure
    		Saturated
    4. Difference between first reference pressure and second reference pressure
    		Less than 0.7 kPa (5.25 mmHg)

    7. Leak check
    Next sequence is run if the following condition is met
    		-
    EVAP pressure when vacuum introduction is complete
    		Lower than second reference pressure

    8. Atmospheric pressure measurement
    EVAP monitor is complete if the following condition is met
    		-
    Atmospheric pressure difference between sequence 1 and 8
    		Within 0.3 kPa (2.25 mmHg)

Purge flow:
Engine
Running
ECT
4.4°C (40°F) or more
IAT
4.4°C (40°F) or more
EVAP pressure sensor
Not detected
EVAP canister purge valve
Not operated by scan tool
EVAP system check
Not operated by scan tool
Battery voltage
10 V or more
Purge duty cycle
8% or more

TYPICAL MALFUNCTION THRESHOLDS


Purge flow:
Both of the following conditions are met
Condition (a) and (b)
(a) EVAP pressure change when purge flow is started
Less than 0.1 kPa (0.75 mmHg)
(b) EVAP pressure change during purge flow when EVAP pressure switching valve ON (closed)
Less than 0.5 kPa (3.75 mmHg)

EVAP VSV stuck open:
EVAP pressure when vacuum introduction is complete
Higher than reference pressure x 0.2

EVAP VSV stuck closed:
EVAP pressure change after EVAP canister purge valve is open
Less than 0.3 kPa (2.25 mmHg)

MONITOR RESULT

Refer to Monitor Result for detailed information (Click here).