Engine Controls - Tests W/o Codes: NVH Mazda 626 GD

ABNORMAL NOISE OR KNOCKING (EFI)

1. Check engine oil level.

Check Electronic Spark Advance (ESA) control system for malfunctioning component. ESA system inspection should include the following components

1. Airflow meter
2. Idle switch
3. Neutral safety switch (A/T)
4. Clutch switch (M/T)
5. EGR position sensor
6. Knock sensor
7. Throttle position sensor
8. Coolant thermosensor
9. Coolant thermoswitch
10. Inhibitor switch (A/T)
11. Electronic Controlled Automatic Transmission (ECAT) unit.

Check turbo system for damage or wear (if equipped). Turbo system inspection should include the following components

1. Air by-pass valve
2. Engine Control Unit (ECU)
3. Intake air thermosensor in airflow meter
4. Knock sensor and knock control unit
5. Turbo wastegate solenoid valve.