{"product_id":"o2-oxygen-sensor-upstream-downstream-for-chevrolet-impala-2004-2005-3-8l","title":"O2 Oxygen Sensor Upstream Downstream for Chevrolet Impala (2004-2005) 3.8L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eDirect-Fit O2 Oxygen Sensor Kit for 2004-2005 Chevrolet Impala (W-Body)\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e Restores closed-loop fuel metering and catalyst monitoring on 2004-2005 Chevrolet Impala (\u003cstrong\u003eW-Body\u003c\/strong\u003e) \u003cstrong\u003e3.8L L36\/L67\u003c\/strong\u003e models.\u003c\/p\u003e\u003ch3\u003eThe Stock Chevrolet Impala Oxygen Sensor Failure\u003c\/h3\u003e\u003cp\u003eOver high mileage, OEM oxygen sensors on the \u003cstrong\u003eW-Body\u003c\/strong\u003e Impala suffer thermal fatigue, internal heater circuit burnout, and zirconia poisoning from oil ash or carbon fouling. When the upstream sensor on the \u003cstrong\u003e3.8L L36\u003c\/strong\u003e or supercharged \u003cstrong\u003eL67\u003c\/strong\u003e turns sluggish, voltage switching slows and corrupts PCM fuel trims. Downstream element degradation then prevents accurate catalyst oxygen-storage monitoring, triggering persistent \u003cstrong\u003eP0131\u003c\/strong\u003e, \u003cstrong\u003eP0135\u003c\/strong\u003e, \u003cstrong\u003eP0141\u003c\/strong\u003e, and \u003cstrong\u003eP0420\u003c\/strong\u003e fault codes.\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:\u003c\/strong\u003e Triggers \u003cstrong\u003eP0134\u003c\/strong\u003e, \u003cstrong\u003eP0135\/P0141\u003c\/strong\u003e (heater circuit), or \u003cstrong\u003eP0171\/P0172\u003c\/strong\u003e fuel trim codes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePoor MPG \u0026amp; Rich Exhaust:\u003c\/strong\u003e Sluggish switching forces rich open-loop fueling and fouls plugs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRough Idle \u0026amp; Emissions Failure:\u003c\/strong\u003e Unstable fuel trims cause surging and failed readiness monitors.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eThe Direct-Fit Heated Zirconia Oxygen Sensor Solution\u003c\/h3\u003e\u003cp\u003eThis matched replacement kit pairs upstream (\u003cstrong\u003e234-4646\u003c\/strong\u003e) and downstream (\u003cstrong\u003e234-4647\u003c\/strong\u003e) direct-fit sensors engineered to restore factory PCM response on naturally aspirated and supercharged \u003cstrong\u003e3.8L\u003c\/strong\u003e exhaust manifolds. Each unit features a fast-light-off ceramic heater and a laser-welded stainless protective shield built to resist moisture shock and exhaust heat soak. Factory-length leads with OEM-style weatherpack connectors plug directly into the \u003cstrong\u003eW-Body\u003c\/strong\u003e chassis harness with zero cutting or splicing.\u003c\/p\u003e\u003ch3\u003eWhat's Included\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e1 Upstream Oxygen Sensor (\u003cstrong\u003e234-4646\u003c\/strong\u003e)\u003c\/li\u003e\n\u003cli\u003e1 Downstream Oxygen Sensor (\u003cstrong\u003e234-4647\u003c\/strong\u003e)\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;\"\u003e2004-2005 Chevrolet Impala\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;\"\u003e3.8L V6 (L36 \/ L67) \/ W-Body\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;\"\u003eEmissions \u0026amp; Sensor Spec\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003eHeated Zirconia (Upstream \u0026amp; Downstream)\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 Bolt-On OEM Replacement\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;\"\u003e234-4646, 234-4647\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003c\/div\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e2004-2005 Chevrolet Impala 3.8L (Naturally Aspirated \u003cstrong\u003eL36\u003c\/strong\u003e) — Upstream \u0026amp; Downstream\u003c\/li\u003e\n\u003cli\u003e2004-2005 Chevrolet Impala 3.8L (Supercharged \u003cstrong\u003eL67\u003c\/strong\u003e) — Upstream \u0026amp; Downstream\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions \u0026amp; Fitment Warnings\u003c\/h3\u003e\u003ch4\u003eDoes this fit the W-Body Impala?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e Fits 2004-2005 Chevrolet Impala (\u003cstrong\u003eW-Body\u003c\/strong\u003e) with the \u003cstrong\u003e3.8L L36\/L67\u003c\/strong\u003e V6. \u003cstrong\u003eConfirm 3.8L engine before ordering; excludes 3.4L V6 models.\u003c\/strong\u003e\u003c\/p\u003e\u003ch4\u003eWill this clear P0135 or P0420 codes?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes, if sensor-induced.\u003c\/strong\u003e Replacing \u003cstrong\u003e234-4646\u003c\/strong\u003e and \u003cstrong\u003e234-4647\u003c\/strong\u003e resolves heater and switching DTCs; persistent \u003cstrong\u003eP0420\u003c\/strong\u003e requires catalyst inspection.\u003c\/p\u003e\u003ch4\u003eAre the electrical connectors plug-and-play?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e Sensors include OEM plugs; apply anti-seize only to threads before installation.\u003c\/p\u003e\u003ch3\u003eThe Chevrolet Precision Standard\u003c\/h3\u003e\u003cp\u003eReplacing both sensors as a matched set restores fuel trim accuracy and emissions readiness on your \u003cstrong\u003eW-Body\u003c\/strong\u003e Impala. Built for exhaust heat durability, this \u003cstrong\u003e3.8L\u003c\/strong\u003e kit ensures CEL-free operation.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":68119471980792,"sku":"DS-EWA0P3UCL","price":48.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/o2-oxygen-sensor-upstream-downstream-for-chevrolet-impala-2004-2005-3-8l-1.jpg?v=1794722912","url":"https:\/\/performancechiptuning.com\/products\/o2-oxygen-sensor-upstream-downstream-for-chevrolet-impala-2004-2005-3-8l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}