DR-22A Oxygen Sensor Operation

1. Connect diagnostic read-out tool to engine test connector. Ensure read/hold switch is in Read position.
2. Start engine and wait two minutes, then place read/hold switch in Hold position.
3. If display on read-out tool is switching between 0 and 1, proceed to Test 23.
4. If display on read-out tool is 0, check engine for vacuum leak, grounded oxygen sensor wire or plugged fuel injector.
5. If display on read-out tool is 1, proceed to step B. DR-22B Rich Engine Operating Condition