{"product_id":"22836-denso-lambda-sensor-air-fuel-ratio-sensor-2345178","title":"22836 Denso Lambda sensor\/Air Fuel Ratio Sensor 2345178","description":"\u003ch2\u003eDenso Air Fuel Ratio Sensor \/ Lambda Sensor 234-5178\u003c\/h2\u003e\n\u003cp\u003eEnsure precise air-fuel mixture control and optimal engine management with the \u003cstrong\u003eDenso Air Fuel Ratio Sensor 234-5178\u003c\/strong\u003e (SKU 22-836). This premium OEM-quality wideband lambda sensor is engineered by Denso to accurately measure the oxygen content of exhaust gases across a wide range of air-fuel ratios, providing the engine control unit (ECU) with critical real-time feedback for precise fuel injection control, optimal combustion efficiency, and reduced emissions. Designed specifically for the Subaru Forester and WRX with the FA20E engine, this sensor ensures dependable engine management performance and long service life.\u003c\/p\u003e\n\u003ch3\u003e\u003cspan\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003e\u003ca style=\"color: rgb(255, 42, 0);\" title=\"PARTS FINDER\" href=\"https:\/\/lm15motorsport.com.au\/pages\/vehicle-catalogue\" rel=\"null noopener\" target=\"_blank\"\u003eCLICK HERE\u003c\/a\u003e \u003c\/span\u003eTO CHECK IF THIS FITS YOUR VEHICLE.\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003ch3\u003eKey Features \u0026amp; Benefits\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDenso OEM Quality\u003c\/strong\u003e - Trusted OEM supplier component built to exacting standards\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSubaru Forester \u0026amp; WRX FA20E Application\u003c\/strong\u003e - Designed specifically for the FA20E engine\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWideband Lambda Measurement\u003c\/strong\u003e - Accurately measures oxygen content across a wide AFR range\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecise Fuel Trim Control\u003c\/strong\u003e - Enables the ECU to maintain the correct air-fuel ratio under all conditions\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImproved Fuel Economy\u003c\/strong\u003e - Supports accurate closed-loop fuelling for maximum efficiency\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReduced Emissions\u003c\/strong\u003e - Ensures correct catalytic converter operation and low exhaust emissions\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFast Light-Off\u003c\/strong\u003e - Integrated heater circuit reaches operating temperature quickly after cold start\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDirect OEM Replacement\u003c\/strong\u003e - Engineered to original specifications\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLong Service Life\u003c\/strong\u003e - Durable construction for extended reliability\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDenso Part Number:\u003c\/strong\u003e 234-5178 (2345178)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSKU:\u003c\/strong\u003e 22-836\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComponent Type:\u003c\/strong\u003e Air Fuel Ratio Sensor \/ Wideband Lambda Sensor (upstream O2 sensor)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrimary Application:\u003c\/strong\u003e Subaru Forester FA20E, Subaru WRX FA20E\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.2 kg (approximate)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eVehicle Compatibility\u003c\/h3\u003e\n\u003cp\u003eThis Denso air fuel ratio sensor is designed for the following models:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eSubaru Forester — FA20E engine\u003c\/li\u003e\n\u003cli\u003eSubaru WRX — FA20E engine\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eAlways verify fitment for your specific vehicle, model year, and sensor position before ordering.\u003c\/p\u003e\n\u003ch3\u003e\u003cspan\u003e\u003cstrong\u003e\u003cspan style=\"color: rgb(255, 42, 0);\"\u003e\u003ca style=\"color: rgb(255, 42, 0);\" title=\"PARTS FINDER\" href=\"https:\/\/lm15motorsport.com.au\/pages\/vehicle-catalogue\" rel=\"null noopener\" target=\"_blank\"\u003eCLICK HERE\u003c\/a\u003e \u003c\/span\u003eTO CHECK IF THIS FITS YOUR VEHICLE.\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h3\u003e\n\u003ch3\u003eOEM Part Number Cross-Reference\u003c\/h3\u003e\n\u003cp\u003eThis Denso air fuel ratio sensor replaces the following OEM part numbers:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e234-5178 (Denso)\u003c\/li\u003e\n\u003cli\u003e22641AA650 (Subaru)\u003c\/li\u003e\n\u003cli\u003eEGO-836 \/ EGO836\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eCommon Symptoms of a Faulty Air Fuel Ratio Sensor\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eCheck engine light illuminated on dashboard\u003c\/li\u003e\n\u003cli\u003eO2 or AFR sensor fault codes (P0130–P0167, P2195–P2199)\u003c\/li\u003e\n\u003cli\u003ePoor fuel economy or rich\/lean running condition\u003c\/li\u003e\n\u003cli\u003eBlack smoke from exhaust (rich) or popping\/lean surge\u003c\/li\u003e\n\u003cli\u003eRough idle or engine hesitation\u003c\/li\u003e\n\u003cli\u003eFailed emissions test\u003c\/li\u003e\n\u003cli\u003eCatalytic converter damage from incorrect AFR over time\u003c\/li\u003e\n\u003cli\u003eSlow or erratic fuel trim corrections\u003c\/li\u003e\n\u003cli\u003eIncreased fuel consumption\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWhat Does an Air Fuel Ratio Sensor Do?\u003c\/h3\u003e\n\u003cp\u003eThe air fuel ratio sensor (AFR sensor), also known as a wideband lambda sensor or upstream oxygen sensor, is a critical engine management component mounted in the exhaust system before the catalytic converter. Unlike a conventional narrowband oxygen sensor that simply switches between rich and lean signals, the wideband AFR sensor can measure the precise air-fuel ratio across a wide range (typically 10:1 to 20:1 AFR), providing the ECU with detailed, linear feedback about combustion quality. The ECU uses this signal to continuously adjust fuel injection pulse width in real time, maintaining the target stoichiometric air-fuel ratio (14.7:1 for petrol) for optimal combustion efficiency, fuel economy, and emissions control. An integrated ceramic heater element brings the sensor to operating temperature rapidly after cold start, enabling closed-loop fuel control to begin within seconds of engine startup. A faulty AFR sensor causes the ECU to rely on default fuel maps, resulting in poor fuel economy, emissions failures, and potential catalytic converter damage.\u003c\/p\u003e\n\u003ch3\u003eWhy Choose Denso Air Fuel Ratio Sensors?\u003c\/h3\u003e\n\u003cp\u003eDenso is one of the world's largest and most trusted OEM automotive component suppliers, and is the original manufacturer of oxygen and air fuel ratio sensors for many major vehicle brands including Subaru, Toyota, and Honda. Denso AFR sensors are engineered to exacting OEM specifications with precision ceramic sensing elements, high-quality heater circuits, and durable construction for long service life in demanding exhaust environments. Choosing a Denso air fuel ratio sensor ensures accurate AFR measurement, reliable ECU feedback, and the confidence of genuine OEM-equivalent quality.\u003c\/p\u003e\n\u003ch3\u003eInstallation Notes\u003c\/h3\u003e\n\u003cp\u003eProfessional installation is recommended for best results. Air fuel ratio sensor replacement requires allowing the exhaust system to cool completely before starting work to avoid burns. Use a dedicated oxygen sensor socket for removal. Apply anti-seize compound to the threads of the new sensor if not pre-applied, taking care not to contaminate the sensor tip. Torque the new sensor to manufacturer specifications — do not overtighten. Reconnect the electrical connector and ensure the wiring harness is routed away from hot exhaust components. Clear any diagnostic trouble codes and allow the engine to complete a full drive cycle to enable the ECU to perform fuel trim adaptation with the new sensor. Verify no fault codes return after the drive cycle.\u003c\/p\u003e\n\u003ch3\u003eWhy Choose LM15 Motorsport?\u003c\/h3\u003e\n\u003cp\u003eWe supply quality OEM and OEM-equivalent engine management components with fast shipping across Australia. Every air fuel ratio sensor is carefully inspected to ensure you receive the correct component for reliable engine management performance. Our team has extensive experience with Subaru FA20E engines and can provide expert advice on oxygen sensor diagnosis and replacement.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNeed help with fitment or installation?\u003c\/strong\u003e Contact our expert team for advice specific to your Subaru Forester or WRX FA20E air fuel ratio sensor requirements.\u003c\/p\u003e","brand":"DENSO","offers":[{"title":"Default Title","offer_id":48237371850903,"sku":"22-836","price":330.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0564\/8672\/3735\/files\/228366WITHLOGO.jpg?v=1788913615","url":"https:\/\/lm15motorsport.com.au\/products\/22836-denso-lambda-sensor-air-fuel-ratio-sensor-2345178","provider":"LM15 Motorsport","version":"1.0","type":"link"}