LEMON Manuals
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Toyota
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1990
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Tercel Base, 2D Hatchback, Standard
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Repair and Diagnosis
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Engine Performance
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System
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Engine Controls - Tests W/Codes - CARBURETED
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Circuit Tests
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Code 21 - Oxygen Sensor Signal
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Probable Causes
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Probable Causes
O2 Sensor or Sensor Circuit
O2 Sensor
ECU
NOTE:
Diagnostic chart not available from manufacturer.