I know it's not a mercedes, but... It is German, does that count?

Wolfsburg edition, it's running somewhat sluggish and is giving off a distinct smell of gas from the exhaust. However, no trouble codes.

Anyone out there have a Jetta or familiar with one? My first guess is O2 sensor. How do I check it? Should the voltage be about .45 at idle warmed up?

TIA

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