Getting a fault code 44 (fuel mixture too lean or too rich).
Tested oxygen sensor voltage output. According to my repair manual, voltage should fluctuate between .2 and .9 volts with engine running warm at 1,500 rpm. I'm getting a steady low reading of .2 volts and below. This may indicate a faulty sensor or an actual fuel mixture problem.
Tested oxygen sensor heater voltage. Ignition on, engine warm but not running. I'm getting zero volts. According to manual, voltage should be 12 volts. Also, according to the manual, the oxygen sensor heater relay controls the power, however this model year is not equipped with a separate oxygen sensor heater relay.
I'd appreciate any comments or information.
Thank you.
John