EGR CONTROL VALVE CHECK <4G63, 4G64>
- Remove the EGR valve and inspect for sticking, carbon deposits, etc. If found clean with a suitable solvent so that the valve seats correctly.
- Connect a hand vacuum pump to the EGR valve.
)
- Apply 67 kPa of vacuum, and check that the vacuum is maintained.
- Apply a vacuum and check the passage of air by blowing through one side of the EGR passage.
| Vacuum |
Passage of air |
|---|---|
| 5.3 kPa or less |
Air is not blown out |
| 27 kPa or more |
Air is blown out |
- Replace the gasket, and tighten to the specified torque.
Tightening torque: 20 ±
2 N·m
EGR CONTROL SOLENOID VALVE CHECK <4G63, 4G64>
NOTE:
When disconnecting the vacuum hose, always make a mark so that it can be reconnected at original position.
When disconnecting the vacuum hose, always make a mark so that it can be reconnected at original position.
- Disconnect the vacuum hose from the solenoid valve.
- Disconnect the harness connector.
- Connect a hand vacuum pump to nipple (A) of the solenoid valve.
)
- Check air tightness by applying a vacuum with voltage applied directly from the battery to the EGR control solenoid valve and without applying voltage.
| Battery voltage |
B nipple condition |
Normal condition |
|---|---|---|
| Not applied |
Open |
Vacuum maintained |
| Applied |
Open |
Vacuum leaks |
| Closed |
Vacuum maintained |
- Measure the resistance between the terminals of the solenoid valve.
)
Standard value: 29 - 35 Ω
(at 20 °C )
EGR VALVE (STEPPER MOTOR) CHECK AND CLEANING <4G69>
Checking the Operation Sound
- Check that the operation sound of the stepper motor can be heard from the EGR valve when the ignition switch is turned ON (without starting the engine).
)
- If the operation sound cannot be heard, inspect the drive circuit of the stepper motor.
NOTE: If the circuit is normal, either the stepper motor or the engine-A/T-ECU may have failed.
Checking the Coil Resistance
- Remove the EGR valve.
- Measure the resistance between terminal No. 2 and either terminal No. 1 or terminal No. 3 of the connector at the EGR valve.
)
Standard value: 20 -
24 Ω
(at 20°C )
- Measure the resistance between terminal No. 5 and either terminal No. 6 or terminal
No. 4 of the connector at the EGR valve.
Standard value: 20 - 24 Ω (atUsing a new gasket, install the EGR valve by tightening its mounting bolts to the specified torque.20°C )
Tightening Torque: 24 ±
4 N·m
Operation Check
- Remove the EGR valve.
- Attach a test wiring harness (special tool MB991658) to the connector at the EGR valve.
)
- Connect the positive (+) terminal of the battery to terminal No. 2.
)
CAUTION- Connect terminals No. 1 and No. 3 to the negative (-) terminal of the battery, in order to test whether the stepper motor vibrates (with a slight shudder), indicating that the stepper motor is operating.
- Connect the positive (+) terminal of the battery to terminal No. 5.
)
CAUTION- Connect terminals No. 4 and No. 6 to the negative (-) terminal of the battery, in order to test whether the stepper motor vibrates (with a slight shudder), indicating that the stepper motor is operating.
- If a vibration can be felt during the test, the stepper motor is normal.
- Using a new gasket, install the EGR valve by tightening its mounting bolts to the specified torque.
Tightening torque: 24 ±
3 N·m
Cleaning the EGR Valve
- Remove the EGR valve and check that the EGR valve is not stuck or clogged with carbon deposits. Use a wire brush to clean the valve if necessary.
CAUTION- Using a new gasket, install the EGR valve by tightening its mounting bolts to the specified torque.
Tightening torque: 24 ±
3 N·m