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Exhaust Gas Recirculation: Testing and Inspection




1. Connect the SSTs (NGS tester) to the DLC-2.
2. Start the engine and let it idle.
3. Select the SIMULATION TEST function on the NGS display.
4. Increase the duty value of the EGR solenoid valve (vacuum) from 0% to 100% using the "EGRVAC".

5. Operate the EGR solenoid valve (vacuum) and inspect if the engine speed becomes unstable or the engine stalls.
- If the engine speed will not change, stop the engine and turn the ignition switch to ON.

6. Increase the duty value of the EGR solenoid valve (vacuum) from 0% to 100% using the "EGRVAC".

7. Operate the EGR solenoid valve (vacuum) and inspect if operation sound of the solenoid valve is heard.
- If the operation sound is heard, inspect the following.
- Loose or damaged vacuum hose
- EGR valve
- EGR solenoid valve (vent)

- If the operation sound is not heard, inspect the following.
- EGR solenoid valve (vacuum)
- Wiring between EGR solenoid valve (vacuum) and PCM terminal 4K