{"product_id":"o2-oxygen-sensor-upstream-downstream-for-toyota-highlander-2001-2003-3-0l","title":"O2 Oxygen Sensor Upstream Downstream for Toyota Highlander (2001-2003) 3.0L","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 2001-2003 Toyota Highlander (XU20)\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e This matched upstream and downstream O2 sensor kit monitors exhaust oxygen levels on 2001-2003 Toyota Highlander \u003cstrong\u003eXU20\u003c\/strong\u003e \u003cstrong\u003e1MZ-FE 3.0L V6\u003c\/strong\u003e models to optimize fuel trim and emissions.\u003c\/p\u003e\u003ch3\u003eThe Stock Toyota Highlander Sensor Failure\u003c\/h3\u003e\u003cp\u003eFactory oxygen sensors on the \u003cstrong\u003eXU20\u003c\/strong\u003e chassis powered by the \u003cstrong\u003e1MZ-FE 3.0L V6\u003c\/strong\u003e endure severe exhaust manifold heat soak and thermal cycling. Over time, internal heater elements frequently burn out, while carbon soot and fuel additives poison the ceramic zirconia sensing element. This sluggish voltage response disrupts closed-loop fuel trims, forcing rich running conditions and triggering ECU fault codes including \u003cstrong\u003eP1135\u003c\/strong\u003e, \u003cstrong\u003eP1155\u003c\/strong\u003e, and \u003cstrong\u003eP0135\u003c\/strong\u003e.\u003c\/p\u003e\u003ch4\u003eCommon Symptoms of a Failing OEM O2 Sensor\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCheck Engine Light \/ DTCs:\u003c\/strong\u003e Stored codes like \u003cstrong\u003eP1135\u003c\/strong\u003e, \u003cstrong\u003eP1155\u003c\/strong\u003e, or \u003cstrong\u003eP0420\u003c\/strong\u003e from heater burnout or slow response.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuel Trim Instability:\u003c\/strong\u003e Rough cold starts, idle surge, and rich exhaust from skewed air-fuel feedback.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompliance \u0026amp; Economy Drop:\u003c\/strong\u003e Reduced fuel mileage and failed emissions tests due to unburned fuel.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eThe Direct-Fit Planar Zirconia Oxygen Sensor Solution\u003c\/h3\u003e\u003cp\u003eThis matched upstream and downstream kit restores factory response rates using thermal-shock-resistant zirconia elements and laser-welded stainless steel sensor housings. Internal dual-layer porous ceramic protection shields the sensing core from exhaust moisture and soot buildup. Pre-terminated OEM-style harness connectors and anti-seize-compatible threaded bungs provide true plug-and-play installation without splicing wires. Replacing both sensors as a matched set directly replaces OEM numbers \u003cstrong\u003e234-9023\u003c\/strong\u003e, \u003cstrong\u003e234-4215\u003c\/strong\u003e, \u003cstrong\u003e234-9009\u003c\/strong\u003e, and \u003cstrong\u003e89467-48011\u003c\/strong\u003e.\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;\"\u003e2001-2003 Toyota Highlander\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;\"\u003e1MZ-FE 3.0L V6 \/ XU20\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 Engine Output\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e220 hp \/ 222 lb-ft\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 (No Cutting or Welding)\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;\"\u003e234-9023, 234-4215, 234-9009, 89467-48011\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003c\/div\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e2001-2003 Toyota Highlander 3.0L\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions \u0026amp; Fitment Warnings\u003c\/h3\u003e\u003ch4\u003eDoes this fit the XU20 Highlander?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e This fits 2001-2003 Toyota Highlander models with the \u003cstrong\u003e1MZ-FE 3.0L V6\u003c\/strong\u003e. \u003cstrong\u003eExcludes 2.4L 4-cylinder trims; confirm engine size before ordering.\u003c\/strong\u003e\u003c\/p\u003e\u003ch4\u003eWill this clear P1135 or P0420 codes?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes, if sensor-related.\u003c\/strong\u003e New sensors resolve heater circuit faults (\u003cstrong\u003eP1135\u003c\/strong\u003e\/\u003cstrong\u003eP1155\u003c\/strong\u003e) and false \u003cstrong\u003eP0420\u003c\/strong\u003e catalyst codes after an ECU reset.\u003c\/p\u003e\u003ch4\u003eIs wiring splicing required for installation?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eNo.\u003c\/strong\u003e Pre-wired OEM connectors install directly; apply anti-seize only to the threads and torque to 30 lb-ft.\u003c\/p\u003e\u003ch3\u003eThe Toyota Precision Standard\u003c\/h3\u003e\u003cp\u003eEngineered for accurate ECU signal feedback, this matched sensor kit maintains clean closed-loop combustion and CEL-free operation on \u003cstrong\u003eXU20\u003c\/strong\u003e platforms. Built to restore emissions compliance and factory throttle response.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":68094238720248,"sku":"DS-EFJQM9OCX","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-toyota-highlander-2001-2003-3-0l-1.jpg?v=1794618137","url":"https:\/\/performancechiptuning.com\/fr\/products\/o2-oxygen-sensor-upstream-downstream-for-toyota-highlander-2001-2003-3-0l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}