Subaru Forester Oxygen Sensor 22690-AA990, remove and replace, no adjustment needed

Subaru Forester 2009–2013 2.5L uses OEM 22690-AA990 oxygen sensor (compatible with some 2014–2016 same-platform models). Monitors exhaust oxygen content and feeds ECU to optimize AF ratio; improves fuel economy and reduces emissions. Removal and replacement are a turnkey swap with no adjustment; installation takes about 30 minutes with basic tools. If idle is unstable or fuel consumption rises, check this sensor first.