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Note On Intermittents

If Code EO13 is stored as a history code, start engine and enter diagnostics. Operate engine at fast idle until AUTO closed loop status light is turned on. Observe parameter of ED33 while manipulating wiring on circuits No. 412 and No. 413. If parameter ED33 changes from a fluctuating voltage to fixed .45 volt, repair intermittent open circuit.

Check circuit No. 413 for a good ground to engine (clean and tighten star washer). Ground circuit No. 413 is located at right side of engine or rear of cylinder head.

Fig 1: PCM Code EO13, Schematic, Right Oxygen Sensor Not Ready
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Fig 2: Flow Chart, PCM Code EO13, Right Oxygen Sensor Not Ready
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