{"product_id":"ignition-coil-and-iridium-spark-plugs-for-jaguar-xjr-2004-2009-4-2l","title":"Ignition Coil and Iridium Spark Plugs for Jaguar XJR (2004-2009) 4.2L","description":"\u003ch2\u003eHigh-Output Ignition Coil and Iridium Spark Plug Kit for 2004-2009 Jaguar XJR\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eDirect-fit replacement ignition tune-up kit:\u003c\/strong\u003e Restores precise secondary ignition delivery and eliminates high-RPM misfires across all 8 cylinders in supercharged AJ-V8 platforms.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock XJR Ignition Breakdown\u003c\/h3\u003e\n\u003cp\u003eThe supercharged AJ34S engine operates under dense charge pressures and intense under-hood thermal cycles. Over time, OEM coil pack epoxy potting degrades, causing internal insulation breakdown, micro-arcing, and secondary voltage leakage. Worn spark plug electrodes further increase electrical resistance, overloading the primary coil circuit and inducing cylinder misfires (P0300–P0308 codes), erratic idle, and boost-cut hesitation.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis ignition kit pairs eight direct-fit coil-on-plug assemblies with eight fine-wire iridium spark plugs. The coil assemblies feature high-grade internal copper windings and reinforced dielectric thermoplastic housings that withstand heat soak and prevent voltage bypass. The fine-wire iridium spark plugs reduce required firing voltage, provide superior anti-fouling capabilities, and stabilize flame kernel growth under boost.\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;\"\u003e2004-2009 Jaguar XJR\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;\"\u003e4.2L SC AJ-V8 (AJ34S) \/ X350, X358\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;\"\u003e400 hp \/ 413 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;\"\u003eUF519, UF533, 6R8312A366AA, C1678, LR016999, AJ83415, 5C1735\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e2004 Jaguar XJR Base Sedan 4.2L V8 Supercharged\u003c\/li\u003e\n  \u003cli\u003e2005 Jaguar XJR Base Sedan 4.2L V8 Supercharged\u003c\/li\u003e\n  \u003cli\u003e2006 Jaguar XJR Base Sedan 4.2L V8 Supercharged\u003c\/li\u003e\n  \u003cli\u003e2007 Jaguar XJR Base Sedan 4.2L V8 Supercharged\u003c\/li\u003e\n  \u003cli\u003e2008 Jaguar XJR Base Sedan 4.2L V8 Supercharged\u003c\/li\u003e\n  \u003cli\u003e2009 Jaguar XJR Base Sedan 4.2L V8 Supercharged\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eThe Jaguar Engineering Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to exact European mechanical tolerances, this direct replacement set integrates seamlessly with the factory engine management system, maintaining proper primary resistance values to guarantee zero check-engine lights and clean combustion.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":50448293527800,"sku":"DS-ELIXOEC4G","price":124.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/ignition-coil-and-iridium-spark-plugs-for-jaguar-xjr-2004-2009-4-2l-1.jpg?v=1788638654","url":"https:\/\/performancechiptuning.com\/products\/ignition-coil-and-iridium-spark-plugs-for-jaguar-xjr-2004-2009-4-2l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}