Subaru OEM Rear Oxygen Sensor Subaru STi 2008-2021 | 22690AA850 CM aggressive exhaust note without excessive

aggressive exhaust note without excessive drone

Each pump individually tested to flow minimum of 400LPH (100gph) @ 40 PSI

7% stiffer than OEM

Part #: 571101

designed around their famous Whiteline Plus series polyurethane bushings

Subaru OEM Rear Oxygen Sensor Subaru STi 2008-2021 | 22690AA850 CM aggressive exhaust note without excessiveFor your: Subaru STi 2008 2021 Rear O2 Sensor The rear oxygen sensor is used to sense oxygen concentration in the exhaust gas. If the air fuel ratio is leaner than the stoichiometric ratio in the mixture (i. e., excessive amount of air), the exhaust gas contains more oxygen. To the contrary, if the fuel ratio is richer than the stoichiometric ratio, the exhaust gas contains almost no oxygen. Detecting the oxygen concentration in exhaust gas using the