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Home >> Land Rover >> 1990 >> Range Rover Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> Code 18: Throttle Position Sensor Input High/Mass Airflow Sensor Low
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Code 18: Throttle Position Sensor Input High/Mass Airflow Sensor Low

NOTE: Use continuity test guide for symbol reference. See Figure .

Test throttle position sensor, see Figure . Test mass air flow sensor, see Figure . See appropriate WIRING DIAGRAMS article. After completing the tests, retest the vehicle to ensure the faults have been rectified. If faults still persist, recheck using Lucas Diagnostic Equipment or Test Book.