{"product_id":"oxygen-sensors-for-mazda-3-5-2011-2015-2-5l-downstream","title":"Oxygen Sensors for Mazda 3 5 (2011-2015) 2.5L Downstream","description":"\u003ch2\u003ePrecision Downstream Oxygen Sensor for 2011-2015 Mazda 3 \u0026amp; Mazda 5\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The Downstream Oxygen Sensor accurately monitors post-catalytic converter exhaust gases on the 2011-2015 Mazda 3 and Mazda 5 to verify emissions compliance, preserve secondary fuel trim balance, and prevent catalytic efficiency error codes.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Mazda Heated O2 Sensor Degradation\u003c\/h3\u003e\n\u003cp\u003eExhaust stream environments subject factory oxygen sensors to severe thermal cycling, moisture, and chemical fouling from unburned hydrocarbons and carbon soot. Over time, the factory post-cat sensor on the \u003cstrong\u003eBL\u003c\/strong\u003e chassis Mazda 3 and \u003cstrong\u003eCW\u003c\/strong\u003e chassis Mazda 5 suffers from poisoned ceramic thimbles and failed internal heater circuits. On high-mileage \u003cstrong\u003eL5-VE\u003c\/strong\u003e 2.5L MZR engines, this degradation causes sluggish millivolt switching, triggering false P0138, P0139, or P0420 DTCs and forcing the PCM into sub-optimal feedback maps that degrade overall engine efficiency.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eEngineered to match factory signal curves, this replacement downstream oxygen sensor features a fast-acting ceramic element housed inside a laser-welded 304 stainless steel body to resist corrosion and thermal shock. Pre-applied anti-seize on precision-machined threads ensures gall-free installation into the exhaust bung. With a high-temperature PTFE fluoropolymer wire harness and OEM-spec weatherproof pin terminals, this direct-fit sensor guarantees instant communication with the factory powertrain control module, maintaining precise signal resolution without wiring modifications.\u003c\/p\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003ctable width=\"100%\" style=\"border-collapse: collapse; border: 1px solid #e0e0e0; font-size: 14px; margin-bottom: 20px;\"\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;\"\u003e2011-2015 Mazda 3, 5\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;\"\u003e\n\u003cstrong\u003eL5-VE\u003c\/strong\u003e (2.5L MZR) \/ \u003cstrong\u003eBL\u003c\/strong\u003e, \u003cstrong\u003eCW\u003c\/strong\u003e\n\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;\"\u003eStock Output\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e167 hp \/ 168 lb-ft\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\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;\"\u003eN\/A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e2011-2013 Mazda 3 2.5L L4 (Downstream)\u003c\/li\u003e\n  \u003cli\u003e2012-2015 Mazda 5 2.5L L4 (Downstream)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eDoes this fit the BL \u0026amp; CW 3,5?\u003c\/strong\u003e\u003cbr\u003e Yes, this is a direct fit for the 2011-2015 Mazda 3,5 equipped with the \u003cstrong\u003eL5-VE\u003c\/strong\u003e engine in the downstream post-catalytic converter position.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill replacing a worn downstream sensor clear a persistent P0420 code?\u003c\/strong\u003e\u003cbr\u003e If the code was triggered by degraded sensor response rather than a failed substrate, this sensor will restore correct cross-counts and clear the condition.\u003c\/p\u003e\n\n\u003ch3\u003eThe Mazda JDM Reliability Standard\u003c\/h3\u003e\n\u003cp\u003eKeep your naturally aspirated MZR powertrain operating at peak thermal and combustion efficiency with components precision-calibrated for Japanese engineered electronic feedback systems.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":50511721169144,"sku":"DS-ENKZ6264Y","price":64.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/oxygen-sensors-for-mazda-3-5-2011-2015-2-5l-downstream-1.jpg?v=1789418474","url":"https:\/\/performancechiptuning.com\/fr\/products\/oxygen-sensors-for-mazda-3-5-2011-2015-2-5l-downstream","provider":"Performance Chip Tuning","version":"1.0","type":"link"}