while cleaning floor about 2 weeks ago, the oxygen sensor green wire was disconnected, so I put it back together and into its slot


i checked the output while driving around and never got above .350 reading on 2v setting digital voltmeter.

does this sound like the o2 sensor needs replaced? I did let car warm up for 10 mins and temp was at 90c but voltage never went above .351 despite lots of flooring on gas pedal.

Possibly the fuel mixture adjustment is too lean? Have you tried any adjustment?

Does the voltage reading CHANGE & go lower?

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the previous emissions test i had to send my MB guy with the car to emissions garage to lean out mixture to make it pass (and promptly readjust so it would drive OK)

but now im emissions EXEMPT

i did not adjust the mixture myself at all as thats really beyond my skills level




the voltage does change and go lower, just not above .351, i will retest this on an upcoming longer trip and report results, the car uses LOTs of oil 1qt/300 miles

so id guess the O2 sensor is plugged up with oil residue and not working 100%