Part 1
2GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P043E,P043F,P2401,P2402,P2419: Evaporative Emission System Reference Orifice Clog Up
Part 1 of 2
DTC P043E - Evaporative Emission System Reference Orifice Clog Up
DTC P043F - Evaporative Emission System Reference Orifice High Flow
DTC P2401 - Evaporative Emission System Leak Detection Pump Control Circuit Low
DTC P2402 - Evaporative Emission System Leak Detection Pump Control Circuit High
DTC P2419 - Evaporative Emission System Switching Valve Control Circuit Low
DTC SUMMARY
HINT: The 0.02 inch orifice is located inside the canister pump module.
DESCRIPTION
While the engine is running, if a predetermined condition (closed-loop, etc.) is met, the purge VSV is opened by the ECM and fuel vapors stored 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 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 EVAP (Evaporative Emission) system leaks and 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 electric vacuum 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 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 always 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 OFF (open) 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.
INSPECTION PROCEDURE
NOTE: The Techstream is required to conduct the following diagnostic troubleshooting procedure.
HINT:
- Using the Techstream monitor results enables the EVAP (Evaporative Emission) system to be confirmed.
- Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
PROCEDURE
1. CONFIRM DTC
(a) Turn the ignition switch off and wait for 10 seconds.
(b) Turn the ignition switch on (IG).
(c) Turn the ignition switch off and wait for 10 seconds.
(d) Connect the Techstream to the DLC3.
(e) Turn the ignition switch on (IG) and turn the tester on.
(f) Select 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 EVAP SYSTEM CHECK (AUTO OPERATION)
NOTICE:
- In the Evaporative System Check (Automatic Mode) series of 5 steps is 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 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 the Evaporative System Check, keep the temperature below 35°C (95°F).
(a) Connect the Techstream to the DLC3.
(b) Clear the DTCs DTC Check / Clear.
(c) Select the following menu items on the tester: Powertrain / Engine and ECT / Utility / Evaporative System Check / Automatic Mode.
(d) After the Evaporative System Check is completed, check for pending DTCs by selecting the following menu items: Powertrain / Engine and ECT / Trouble Codes / Pending.
HINT: If no pending DTC is displayed, perform the Monitor Confirmation after this 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 EVAP SYSTEM CHECK (MANUAL OPERATION)
NOTICE:
- In the Evaporative System Check (Manual Mode), the series of 5 Evaporative System Check steps is performed manually by the Techstream.
- 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 the Evaporative System Check, keep the temperature below 35°C (95°F).
(a) Connect the Techstream to the DLC3.
(b) Clear the DTCs DTC Check / Clear.
(c) Select the following menu items: Powertrain / Engine and ECT / Utility / Evaporative System Check / Manual Mode.
NEXT -- Continue to next step.
4. PERFORM EVAP SYSTEM CHECK (STEP 1/5)
(a) Check the EVAP pressure in step 1/5.
Result:
*: The DTCs relating to the EVAP system displayed on the Techstream when checking.
B -- REPLACE CHARCOAL CANISTER ASSEMBLY
A -- Continue to next step.
5. PERFORM EVAP SYSTEM CHECK (STEP 1/5 TO 2/5)
(a) Check the EVAP pressure in steps 1/5 and 2/5.
Result:
*: The DTCs related to the EVAP system are displayed on the Techstream when checking.
HINT: The first 0.02 inch leak pressure standard is the value determined in step 2/5.
B -- PERFORM ACTIVE TEST USING TECHSTREAM (FOR CANISTER PUMP MODULE (VACUUM PUMP))
A -- Continue to next step.
6. PERFORM EVAP SYSTEM CHECK (STEP 2/5)
HINT: Make a note of the pressures checked in steps (a) and (b) below.
(a) Check the EVAP pressure 4 seconds after the vacuum pump is activated*1 (Step (a)).
(b) Check the EVAP pressure again when it has stabilized. This pressure is the 0.02 inch leak pressure standard (Step (b)).
*1: The vacuum pump begins to operate at the time step 2/5 starts.
Result:
*2: 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 CHARCOAL CANISTER ASSEMBLY
B -- PERFORM EVAP SYSTEM CHECK (STEP 3/5)
A -- Continue to next step.
7. PERFORM EVAP SYSTEM CHECK (STEP 2/5 TO 3/5)
(a) Check the EVAP pressure increase in step 3/5.
Result:
*: The DTCs related to the EVAP system are displayed on the Techstream when checking.
C -- REPLACE CHARCOAL CANISTER ASSEMBLY
B -- PERFORM ACTIVE TEST USING TECHSTREAM (FOR VENT VALVE)
Continue to Part 2 [1][2][3][4][5]P043E