{"product_id":"high-performance-ignition-coils-for-buick-rainier-2004-2005-5-3l","title":"High Performance Ignition Coils for Buick Rainier (2004-2005) 5.3L","description":"\u003ch2\u003eHigh-Output Ignition Coils for 2004-2005 Buick Rainier (5.3L LM4\/LH6 \/ GMT360)\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eDirect OEM-replacement electronic ignition coils designed to restore reliable spark delivery and resolve misfires.\u003c\/strong\u003e Restores proper combustion efficiency by replacing degraded factory coil packs to eliminate rough idle, hesitation, and misfire codes under load.\u003c\/p\u003e\n\u003ch3\u003eThe Stock Rainier Ignition Shortcomings\u003c\/h3\u003e\n\u003cp\u003eThe factory D585-style ignition coils on the 5.3L Vortec V8 are notorious for thermal degradation over time. Positioned directly above the exhaust manifolds, the OEM epoxy potting material undergoes severe heat cycling. This leads to micro-cracking in the internal windings and secondary winding failure. As resistance increases, spark energy drops, leading to primary circuit faults, P0300 random misfire codes, incomplete combustion, and a noticeable drop in torque, particularly when towing or under heavy throttle inputs where dense air-fuel mixtures require maximum voltage to jump the spark plug gap.\u003c\/p\u003e\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThese replacement electronic coils feature reinforced epoxy resin to prevent thermal breakdown and electrical arcing under high under-hood temperatures. The internal copper windings are precision-wound to match OEM resistance specifications, ensuring direct communication with the PCM without triggering false CELs. Featuring a heavy-duty 4-blade terminal design, oval female connectors, and a reliable bolt-on mounting configuration, they guarantee a secure electrical connection and simple installation. This direct-fit upgrade restores the required kilovolt output for complete cylinder burn, smoothing out the idle and returning factory throttle response and fuel economy to the GMT360 chassis.\u003c\/p\u003e\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;\"\u003e2004-2005 Buick Rainier\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 \u0026amp; LH6 Vortec V8 \/ GMT360\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;\"\u003e290-300 hp \/ 325-330 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;\"\u003eD585, 10457730, 19005218, UF262\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e2004 Buick Rainier 5.3L V8\u003c\/li\u003e\n\u003cli\u003e2005 Buick Rainier 5.3L V8\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eThe Buick Durability Standard\u003c\/h3\u003e\n\u003cp\u003eBuilt to handle the demanding loads of the GMT360 platform, these coils ensure reliable towing performance, sustained torque delivery, and consistent all-weather ignition for your 5.3L Rainier.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":48234302537976,"sku":"DS-EHCDLLMYQ","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-buick-rainier-2004-2005-5-3l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}