His FAQ is designed to answer most of the commonly asked ...

O2 Sensor Operation I have a 1982 924 and soldered a shielded 'pig tail' at the K-Jetronic control box under the dash so I could hook up a Digital Voltmeter to monitor the O2 Sensor voltage. after warm up the voltage was .75mV at idle but would vary wildly from .05 to .8 volts going down the road. ................
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