{"product_id":"o2-oxygen-sensor-upstream-downstream-for-subaru-forester-2011-2013-2-5l-non-turbo","title":"O2 Oxygen Sensor Upstream Downstream for Subaru Forester (2011-2013) 2.5L Non-Turbo","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eDirect-Fit Upstream \u0026amp; Downstream O2 Sensor Kit for 2011-2013 Subaru Forester (SH)\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e This matched upstream and downstream oxygen sensor kit monitors exhaust air-fuel ratio and catalyst efficiency on 2011-2013 \u003cstrong\u003eSH\u003c\/strong\u003e Forester \u003cstrong\u003eFB25 2.5L DOHC\u003c\/strong\u003e engines.\u003c\/p\u003e\u003ch3\u003eThe Stock Subaru Forester Sensor Failure\u003c\/h3\u003e\u003cp\u003eOn the \u003cstrong\u003eSH\u003c\/strong\u003e Forester equipped with the \u003cstrong\u003eFB25 2.5L DOHC\u003c\/strong\u003e engine, factory upstream air-fuel and downstream oxygen sensors endure severe thermal cycling inside the exhaust stream. Over time, carbon buildup, flat-four oil ash, and internal heater element wear cause sluggish voltage switching or open circuits. When sensor output drifts, the ECM loses accurate closed-loop lambda feedback and logs fault codes such as \u003cstrong\u003eP0133\u003c\/strong\u003e, \u003cstrong\u003eP0031\u003c\/strong\u003e, or \u003cstrong\u003eP0420\u003c\/strong\u003e.\u003c\/p\u003e\u003ch4\u003eCommon Symptoms of a Failing OEM Oxygen Sensor\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheck Engine Light \/ DTCs:\u003c\/strong\u003e Slow response or heater faults trigger \u003cstrong\u003eP0133\u003c\/strong\u003e, \u003cstrong\u003eP0171\u003c\/strong\u003e, \u003cstrong\u003eP0031\u003c\/strong\u003e, or \u003cstrong\u003eP0420\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRich Fuel Trims:\u003c\/strong\u003e Skewed lambda feedback forces open-loop fueling, fouling plugs and hurting economy.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEmissions Failure:\u003c\/strong\u003e Sluggish sensor switching causes rough idle and failed OBD-II readiness monitors.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eThe Direct-Fit Heated Zirconia Sensor Solution\u003c\/h3\u003e\u003cp\u003eReplacing both sensors together restores factory closed-loop fuel control across the \u003cstrong\u003eFB25 2.5L DOHC\u003c\/strong\u003e exhaust system. Each unit uses a corrosion-resistant stainless housing, high-temp ceramic sensing element, and precision internal heater for fast cold-start light-off. Factory-length shielded leads and keyed OE connectors plug directly into the \u003cstrong\u003eSH\u003c\/strong\u003e harness without splicing. Built to OE specs for \u003cstrong\u003e234-9109\u003c\/strong\u003e, \u003cstrong\u003e234-4513\u003c\/strong\u003e, and \u003cstrong\u003e22641-AA610\u003c\/strong\u003e, this matched kit restores accurate air-fuel stoichiometry.\u003c\/p\u003e\u003ch3\u003eWhat's Included\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e1 Upstream Oxygen Sensor\u003c\/li\u003e\n\u003cli\u003e1 Downstream Oxygen Sensor\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\u003cdiv style=\"overflow-x: auto; margin-bottom: 20px;\"\u003e\u003ctable width=\"100%\" style=\"border-collapse: collapse; border: 1px solid #e0e0e0; font-size: 14px; min-width: 300px;\"\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eFitment\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e2011-2013 Subaru Forester\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eEngine \/ Chassis\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003eFB25 2.5L DOHC \/ SH\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eSensor Architecture\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003eUpstream AFR \u0026amp; Downstream Heated O2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eInstallation Type\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003eDirect OEM Thread-In (Plug-and-Play)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eReplaces OEM Part #\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e234-9109, 234-4513, 22641-AA610\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003c\/div\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e2011-2013 Subaru Forester 2.5L Naturally Aspirated (DOHC Non-Turbo) — Uses 2 sensors (1 upstream, 1 downstream)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExclusions:\u003c\/strong\u003e Does NOT fit 2.5L turbocharged Forester XT or Subaru XV Crosstrek\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions \u0026amp; Fitment Warnings\u003c\/h3\u003e\u003ch4\u003eDoes this fit the SH Forester?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e Direct fit for the 2011-2013 Subaru Forester with the \u003cstrong\u003eFB25 2.5L DOHC\u003c\/strong\u003e non-turbo engine. \u003cstrong\u003eExcludes the 2.5L turbo Forester XT and XV Crosstrek; confirm engine before ordering.\u003c\/strong\u003e\u003c\/p\u003e\u003ch4\u003eWill this clear P0133 or P0420 codes?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eIt resolves sensor faults.\u003c\/strong\u003e New sensors clear response and heater codes like \u003cstrong\u003eP0133\u003c\/strong\u003e and \u003cstrong\u003eP0031\u003c\/strong\u003e, though a returning \u003cstrong\u003eP0420\u003c\/strong\u003e indicates a worn catalytic converter.\u003c\/p\u003e\u003ch4\u003eAre OEM-style connectors pre-installed?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e Both sensors come pre-terminated for plug-and-play installation; keep the sensing element clean during threading and torque to spec.\u003c\/p\u003e\u003ch3\u003eThe Subaru Precision Standard\u003c\/h3\u003e\u003cp\u003eEngineered for flat-four ECM precision, this matched kit keeps your \u003cstrong\u003eSH\u003c\/strong\u003e Forester in clean closed-loop stoichiometry with zero check engine lights. Reliable sensor feedback maintains emissions compliance and smooth throttle response.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":68119396253944,"sku":"DS-EGBX9M40K","price":49.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/o2-oxygen-sensor-upstream-downstream-for-subaru-forester-2011-2013-2-5l-non-turbo-1.jpg?v=1794719942","url":"https:\/\/performancechiptuning.com\/products\/o2-oxygen-sensor-upstream-downstream-for-subaru-forester-2011-2013-2-5l-non-turbo","provider":"Performance Chip Tuning","version":"1.0","type":"link"}