Lexus Troubleshooting Questions? Ask a Lexus Expert
Hello, Eddie here and I will do my best to help. Bank 1 sensor 1, is the oxygen sensor, (or Air/Fuel ratio sensor as Toyota or Lexus calls it) that is in the back of the engine, closest to the cylinder head. It is BEFORE the catalytic converter, but on the rear of the engine, as the number 1 cylinder is the cylinder closest to the passenger inner fender but on the BACK of the engine. Refer to this diagram. Let me know if you have any further questions. Thank you.
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