BDFHYK Oxygen Sensor Upstream Downstream O2 Sensor, Compatible with Lexus GS430 4.3L 2001-2007, SC430 4.3L 2002-2010, Compatible with Toyota FJ Cruiser 4.0L 2010-2012, 234-4138 1PCS

This BDFHYK 234-4138 O2 sensor is an OE-style aftermarket replacement for listed Lexus GS430 4.3L, Lexus SC430 4.3L, Toyota FJ Cruiser 4.0L and Toyota 4Runner 4.7L applications. The exact upstream or downstream position varies by vehicle configuration. Before ordering, confirm the listed year and engine, original 89465-series sensor number, connector, wiring, lead length, emissions configuration and exhaust location. A Check Engine Light or stored diagnostic code alone does not prove oxygen sensor failure.

234-4138 O2 Sensor Fitment for Lexus and Toyota

234-4138 O2 Sensor Interchange References

Replacement references include 234-4138, 8946550120, 8946560150 and 8946560430. Match the reference together with the connector and original exhaust location.

234-4138 Upstream and Downstream Position Check

Position is application-dependent. Confirm the original sensor location with vehicle-specific service information and do not assign a universal Bank/Sensor number from the product family alone.

234-4138 O2 Sensor Diagnosis Before Replacement

Inspect the connector, wiring, heater circuit, related fuse, exhaust leaks, intake or fuel-control faults, misfires and catalyst operation before replacement. P0420 or P0430 does not automatically prove an oxygen sensor is defective.

234-4138 O2 Sensor Installation Notes

• Allow the exhaust system to cool before service.
• Use an O2 sensor socket or suitable wrench.
• Compare the connector, lead length and original number with the removed sensor.
• Inspect bung threads and start the sensor by hand.
• Use anti-seize only when permitted by the sensor instructions.
• Tighten to the applicable service specification and route the harness safely.

234-4138 O2 Sensor Package Contents

• 1 × BDFHYK oxygen sensor

Important: This is an OE-style aftermarket replacement, not a factory-branded part.