{"product_id":"o2-oxygen-sensor-upstream-downstream-for-chevrolet-avalanche-2002-2006-5-3l","title":"O2 Oxygen Sensor Upstream Downstream for Chevrolet Avalanche (2002-2006) 5.3L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eDirect-Fit Upstream \u0026amp; Downstream O2 Oxygen Sensor Kit for 2002-2006 Chevrolet Avalanche (GMT800)\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e This 4-piece upstream and downstream oxygen sensor kit restores closed-loop air-fuel ratio monitoring and catalyst efficiency tracking on the \u003cstrong\u003eGMT800\u003c\/strong\u003e 2002-2006 Chevrolet Avalanche 1500 equipped with the \u003cstrong\u003eLM7 5.3L V8\u003c\/strong\u003e.\u003c\/p\u003e\u003ch3\u003eThe Stock Chevrolet Avalanche Sensor Failure\u003c\/h3\u003e\u003cp\u003eFactory zirconia sensors on the \u003cstrong\u003eGMT800\u003c\/strong\u003e platform suffer thermal fatigue from continuous 1,400°F+ exhaust exposure on the \u003cstrong\u003eLM7 5.3L V8\u003c\/strong\u003e. Over time, platinum electrode contamination, oil-ash fouling, and heater-circuit burnout slow voltage switching between rich and lean states. Sluggish upstream response skews PCM fuel trims, while degraded downstream sensors trigger \u003cstrong\u003eP0135\u003c\/strong\u003e, \u003cstrong\u003eP0155\u003c\/strong\u003e, or \u003cstrong\u003eP0420\/P0430\u003c\/strong\u003e faults across Bank 1 and Bank 2.\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 \u0026amp; DTCs:\u003c\/strong\u003e Stored fault codes such as \u003cstrong\u003eP0135\u003c\/strong\u003e, \u003cstrong\u003eP0141\u003c\/strong\u003e, \u003cstrong\u003eP0155\u003c\/strong\u003e, or \u003cstrong\u003eP0171\/P0174\u003c\/strong\u003e from open heater circuits and slow sensor switching.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuel Trim Drift:\u003c\/strong\u003e Delayed voltage transitions force open-loop enrichment, causing rough idle, black exhaust soot, and sluggish throttle response.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFailed Emissions \u0026amp; MPG Loss:\u003c\/strong\u003e Inaccurate exhaust oxygen readings cut highway fuel economy and prevent OBD-II readiness monitors from setting.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eThe Direct-Fit 4-Sensor Oxygen Kit Solution\u003c\/h3\u003e\u003cp\u003eReplacing all four sensors simultaneously as a matched set balances Bank 1 and Bank 2 fuel-trim feedback across the \u003cstrong\u003eLM7 5.3L V8\u003c\/strong\u003e exhaust stream. Each unit features a laser-welded stainless housing, ceramic zirconia sensing element, and PTFE-sealed breather cable to resist moisture and underbody salt corrosion. Pre-terminated OEM connectors ensure plug-and-play fitment matching interchange numbers \u003cstrong\u003e234-4012\u003c\/strong\u003e and \u003cstrong\u003e250-24012\u003c\/strong\u003e with no wire splicing.\u003c\/p\u003e\u003ch3\u003eWhat's Included\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e2 Upstream Oxygen Sensors\u003c\/li\u003e\n\u003cli\u003e2 Downstream Oxygen Sensors\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;\"\u003e2002-2006 Chevrolet Avalanche (1500)\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;\"\u003eLM7 5.3L V8 \/ GMT800\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;\"\u003eHeated 4-Wire Zirconia (2 Upstream \/ 2 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 Thread-In OEM Replacement (Plug-and-Play, No Splicing)\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;\"\u003e250-24012, 21006, 24626, 13026, 13423, 15637, 15703, 234-4012\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003c\/div\u003e\u003ch3\u003eCompatibility\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e2002-2006 Chevrolet Avalanche 1500 5.3L (\u003cstrong\u003eGMT800\u003c\/strong\u003e) — 2 Upstream \u0026amp; 2 Downstream Positions\u003c\/li\u003e\n\u003cli\u003eExcludes 6.0L and 8.1L engines (different catalytic converter and sensor layout)\u003c\/li\u003e\n\u003cli\u003eExcludes 2007-2013 Chevrolet Avalanche 5.3L models\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions \u0026amp; Fitment Warnings\u003c\/h3\u003e\u003ch4\u003eDoes this fit the GMT800 Avalanche?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e This is a direct fit for the 2002-2006 Chevrolet Avalanche 1500 equipped with the \u003cstrong\u003eLM7 5.3L V8\u003c\/strong\u003e engine. \u003cstrong\u003eExcludes 6.0L, 8.1L, and 2007-2013 5.3L Avalanche models; confirm engine before ordering.\u003c\/strong\u003e\u003c\/p\u003e\u003ch4\u003eWill this clear P0135, P0155, or P0420\/P0430 codes?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes, when caused by faulty sensors.\u003c\/strong\u003e Restoring heater resistance and switching speed clears \u003cstrong\u003eP0135\u003c\/strong\u003e, \u003cstrong\u003eP0155\u003c\/strong\u003e, and false \u003cstrong\u003eP0420\/P0430\u003c\/strong\u003e codes after a drive cycle, provided the catalytic converter substrate is intact.\u003c\/p\u003e\u003ch4\u003eAre the connectors plug-and-play for installation?\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eYes.\u003c\/strong\u003e All four sensors feature factory-style connectors that plug straight into the OEM harness with no cutting or splicing required; torque threaded sensors to factory spec.\u003c\/p\u003e\u003ch3\u003eThe Chevrolet Heavy-Duty Standard\u003c\/h3\u003e\u003cp\u003eBuilt for the towing loads and high underbody exhaust temperatures of the \u003cstrong\u003eGMT800\u003c\/strong\u003e Avalanche 1500, this matched 4-sensor kit restores crisp closed-loop fuel metering. Reliable voltage feedback protects your catalytic converters and keeps the \u003cstrong\u003eLM7 5.3L V8\u003c\/strong\u003e operating efficiently under load.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":68119431839992,"sku":"DS-EEN86QTA9","price":96.95,"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-avalanche-2002-2006-5-3l-1.jpg?v=1794721525","url":"https:\/\/performancechiptuning.com\/products\/o2-oxygen-sensor-upstream-downstream-for-chevrolet-avalanche-2002-2006-5-3l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}