{"product_id":"high-performance-ignition-coils-for-gmc-envoy-xl-xuv-2003-2004-5-3l","title":"High Performance Ignition Coils for GMC Envoy XL XUV (2003-2004) 5.3L","description":"\u003ch2\u003eHigh-Output Ignition Coils for 2003-2004 GMC Envoy XL \/ XUV (5.3L LM4 \/ GMT370)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e Replaces degrading OEM ignition coils to restore spark voltage, eliminate high-RPM misfires, and improve fuel combustion efficiency.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Envoy Ignition Degradation\u003c\/h3\u003e\n\u003cp\u003eThe OEM ignition coils on the 5.3L LM4 V8 are notoriously susceptible to thermal degradation due to excessive heat soak from the aluminum engine block and their close proximity to the exhaust manifolds. Over thousands of miles of intense thermal cycling, the factory epoxy potting material becomes brittle and develops structural micro-cracks. This degradation allows moisture intrusion and internal electrical arcing, which manifests mechanically as erratic voltage drops, noticeable hesitation under heavy acceleration, rough idling, and persistent cylinder misfire codes (P0300 series). This is especially prevalent when the engine is subjected to heavy loads or extended towing conditions where under-hood temperatures peak.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThese upgraded electronic ignition coils are engineered specifically to address the thermal limitations of the factory GM units. Constructed with a high-temperature epoxy formulation and premium-grade internal copper windings, they significantly reduce internal resistance and prevent the insulation breakdown that plagues older D585\/UF262 coil packs. The robust bolt-on design features precise 4-terminal blade connectors to ensure a secure, weather-tight electrical connection. By utilizing advanced internal circuitry, these coils guarantee a consistent, high-energy spark across the entire RPM range. Eliminating voltage leaks and maximizing spark dwell time restores factory throttle response, stabilizes the idle, and ensures reliable ignition during high-stress driving.\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;\"\u003e\n  \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003ctd style=\"padding:8px;\"\u003e\u003cstrong\u003eFitment\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:8px;\"\u003e2003-2004 GMC Envoy XL \/ XUV\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd style=\"padding:8px;\"\u003e\u003cstrong\u003eEngine \/ Chassis\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:8px;\"\u003e5.3L LM4 V8 \/ GMT370 \u0026amp; GMT305\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003ctd style=\"padding:8px;\"\u003e\u003cstrong\u003eStock Output\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:8px;\"\u003e290 hp \/ 325 lb-ft (Approx)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd style=\"padding:8px;\"\u003e\u003cstrong\u003ePart Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:8px;\"\u003e920-1020, SKIC121, CUF262, 82863, 48658, 178-8399, GN10119, IC413, 353N, 3-566, 8263, 82633, 8286, U5183, 410001, C-593, 10457730, 19005218, D585, 140040ACC, 3IC221, 50016, 36-1205, 5113, 2505-247733, E254, C1251, 12563293, 5C1082, UF262T, 673-7101, 52-1647, EBC1347, 26C1048, IGC0127\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e2003 GMC Envoy XL 5.3L V8\u003c\/li\u003e\n  \u003cli\u003e2004 GMC Envoy XL 5.3L V8\u003c\/li\u003e\n  \u003cli\u003e2004 GMC Envoy XUV 5.3L V8\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eThe GMC Durability Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to withstand the demanding conditions of payload hauling and continuous towing, these precision replacement coils ensure your Envoy maintains dependable V8 power, optimal fuel economy, and factory-grade reliability without triggering a Check Engine Light.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":48234291593464,"sku":"DS-E7OGUVWKL","price":139.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/Ignition-Chevy-V8.jpg?v=1776103425","url":"https:\/\/performancechiptuning.com\/products\/high-performance-ignition-coils-for-gmc-envoy-xl-xuv-2003-2004-5-3l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}