Exhaust Gas Recirculation: Testing and Inspection

Using SST-Engine Signal Monitor
1. Remove the ECM.




2. Connect the SST to the ECM.
3. Verify that the engine is cold condition.
4. Start the engine and hold the engine speed over 3,000 rpm.
5. Measure the voltage at ECM terminals 4G and 4K by using a voltmeter.

Specification: Battery positive voltage

6. Warm up the engine to normal operating temperature and let it idle.




7. Position the vehicle on a chassis roller and shift the selector lever to D.
8. Increase the engine speed over 3,000 rpm and hold it.
9. Measure the voltage at ECM terminals 4G and 4K by using a voltmeter.

Specification: Approx. 11 V

10. Ground ECM terminal 4K by using a jumper wire.
11. Verify that the engine runs roughly or stalls at idle.
12. If not as specified, inspect following:
- ECM terminal 3Q voltage (Engine coolant temperature sensor)
- ECM terminal 10 voltage (Vehicle speed sensor)
- ECM terminal 4AH, 4AL voltage (Crankshaft position sensor)
- EGR control valve
- EGR solenoid valve (vacuum)
- EGR solenoid valve (vent)
- EGR valve position sensor
- Vacuum hose for damage or looseness

Using SST-New Generation Star Tester (NGS) and Engine Signal Monitor)
1. Remove the ECM.
2. Connect the engine signal monitor to the ECM.




3. Connect the NGS to the data link connector-2.
4. Verify that the engine is cold condition.
5. Start the engine and hold the engine speed over 3,000 rpm.
6. Measure the voltage at ECM terminals 4G and 4K by using a voltmeter.

Specification: Battery positive voltage

7. Warm up the engine to normal operating temperature and let it idle.
8. Position the vehicle on a chassis roller and shift the selector lever to D.
9. Increase the engine speed over 3,000 rpm and hold it.
10. Measure the voltage at ECM terminals 4G and 4K by using a voltmeter.

Specification: Approx. 11 V




11. Select the SIMULATION TEST function of the NGS.
12. Select "EGRVAC" on the NGS display.
13. Set the duty value at 100%.
14. Verify that the engine runs roughly or stalls at idle.
15. If not as specified, turn off the ignition switch.
16. Turn the ignition switch to ON.
17. Using the SIMULATION TEST function, check the operation sound of the EGR solenoid valve (vacuum, vent).
18. If the operation sound is heard, inspect following
- ECM terminal 30 voltage (Engine coolant temperature sensor)
- ECM terminal 10 voltage (Vehicle speed sensor)
- ECM terminal 4AL, 4AH voltage(Crankshaft position sensor)
- EGR control valve
- EGR valve position sensor
- Vacuum hose for damage or looseness
19. If the operation sound is not heard, inspect EGR solenoid valves (vacuum and vent).