Please verify the exact vehicle model and part number before purchase to ensure proper fit. Compatibility and part numbers - For Toyota vehicles: Corolla, Highlander, Matrix - O2 sensor part numbers: 89467-07030 and 234-9008 What this part does - Oxygen sensor (O2 sensor / lambda sensor) monitors the exhaust gas oxygen level and provides critical feedback to the engine management system to balance the air-fuel ratio. - It is a key feedback sensor in the EFI engine control system, enabling accurate fueling and emissions control. Why you may need it - Replacing a tired or faulty O2 sensor can restore engine performance, improve throttle response, and enhance fuel economy. - Proper sensor operation supports reduced emissions and better overall engine efficiency. 2-3 practical use scenarios - Scenario 1: Your vehicle exhibits reduced fuel efficiency or rough idle due to a failing O2 sensor; replacement can restore efficiency and smooth operation. - Scenario 2: Routine maintenance on older Toyota models to maintain optimal air-fuel ratio and emissions performance. - Scenario 3: Diagnostic follow-up for codes related to O2 sensor faults or lean/rich running conditions, as part of a correct repair. Notes - Please confirm compatibility by vehicle model and part number before ordering to ensure proper fit.