[jgonzales]

Does anybody know if the Oxygen Sensor "Sensor 1 Bank 1" is located before the cat, or after the cat?...


...and what would be the best replacement?...bosch?

Sensor 1 is before the cat, sensor 2 is after.. and I would definitely stay away from the Bosch sensor. Get a Denso or Delco if possible, Denso is most likely the company who makes the OE sensor.