[2] PERIODIC INSPECTION AND MAINTENANCE - - OPERATIONS AFTER ENGINE IS WARMED UP - E8. CHECK EXHAUST GAS RECIRCULATION (EGR) SYSTEM | PRINT PAGE / INDEX / PRIOR / NEXT

E8. CHECK EXHAUST GAS RECIRCULATION (EGR) SYSTEM
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. 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 (at 20°C) Using a new gasket, install the EGR valve by tightening its mounting bolts to the specified torque. 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 Connecting battery voltage to the EGR valve for a long term could damage the coil. 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 Connecting battery voltage to the EGR valve for a long term could damage the coil. 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 Do not use a solvent or detergent, which could enter the motor and cause it to malfunction. Using a new gasket, install the EGR valve by tightening its mounting bolts to the specified torque. Tightening torque: 24 ± 3 N·m

[2] PERIODIC INSPECTION AND MAINTENANCE - - OPERATIONS AFTER ENGINE IS WARMED UP - E8. CHECK EXHAUST GAS RECIRCULATION (EGR) SYSTEM | PRINT PAGE / INDEX / PRIOR / NEXT

©2004 Mitsubishi Motors Corporation