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Code 44: Lean Exhaust Indication: Notes

Sensor acts like an open sensor circuit and produces no voltage when exhaust temperature is less than 600°F (316°C). An open sensor circuit or cold sensor causes "open loop" operation.

NOTE: Test numbers refer to test numbers on diagnostic chart.

Test Number 1)  Code 44 sets when O2 sensor signal at ECM is less than .2 volt for 50 seconds or more and system is operating in "closed loop".