Subaru Oxygen Sensor 234-4445, replaces 22690-AA810 22690-AA81A

This oxygen sensor (model 234-4445) is designed for 2005-2009 Subaru Legacy, Outback 2.5L naturally aspirated engines, and also fits 2006-2010 Subaru Forester 2.5X and 2.5XT. It monitors exhaust oxygen content, feeds air-fuel ratio signals to the ECU, ensuring combustion efficiency and emissions compliance. OEM numbers include 22690-AA810, 22690-AA81A, and 234-4445 for quick cross-check in stock. Replacement difficulty medium; use a dedicated O2 sensor socket to avoid thread damage; apply anti-seize to extend life. This sensor is a KLP standard part, direct OEM replacement, no programming or calibration required; suitable for bulk purchase to reduce repair costs.