{"product_id":"ignition-coil-and-iridium-spark-plugs-for-jaguar-xk8-2003-2006-4-2l","title":"Ignition Coil and Iridium Spark Plugs for Jaguar XK8 (2003-2006) 4.2L","description":"\u003ch2\u003eDirect-Fit Ignition Coil and Iridium Spark Plug Service Kit for 2003-2006 Jaguar XK8\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e Replaces degraded factory coil packs and worn plugs with matched, high-dielectric coil-on-plug assemblies and fine-wire iridium spark plugs to restore factory secondary ignition voltage, cure misfires, and stabilize idle quality.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock XK8 Thermal Breakdown and Secondary Voltage Loss\u003c\/h3\u003e\n\u003cp\u003eThe Jaguar AJ34 engine bay suffers from severe thermal cycling under the coil cover trays, leading to micro-cracking in factory epoxy insulation and internal copper winding degradation over time. This breakdown causes high-load secondary voltage leakage, intermittent P0300-P0308 misfires, rough idle, and unburned fuel entering the catalytic converters. Concurrently, standard electrode erosion widens the spark gap, overstressing aging coil packs and triggering hesitation under acceleration.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis comprehensive tune-up kit features eight direct-replacement ignition coils engineered with high-grade copper windings and silicone dielectric boots that resist heat soak up to 400°F. Paired with eight fine-wire iridium spark plugs, the setup requires lower ignition voltage to arc, ensuring rapid flame propagation and reliable combustion under high cylinder pressures. Heavy-duty blade terminals guarantee clean signal delivery from the ECM with zero wiring modifications.\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;\"\u003e2003-2006 Jaguar XK8\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 AJ-V8 (AJ34) \/ X100\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;\"\u003e294 hp \/ 303 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\u003e2003 Jaguar XK8 Base Coupe \u0026amp; Convertible 4.2L V8\u003c\/li\u003e\n  \u003cli\u003e2004 Jaguar XK8 Base Coupe \u0026amp; Convertible 4.2L V8\u003c\/li\u003e\n  \u003cli\u003e2005 Jaguar XK8 Base Coupe \u0026amp; Convertible 4.2L V8\u003c\/li\u003e\n  \u003cli\u003e2006 Jaguar XK8 Base Coupe \u0026amp; Convertible 4.2L V8\u003c\/li\u003e\n  \u003cli\u003e2006 Jaguar XK8 Victory Edition Coupe \u0026amp; Convertible 4.2L V8\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eThe Jaguar Precision Ignition Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to meet stringent European OBD-II parameters, this ignition service kit prevents phantom fault codes and keeps your grand tourer operating with smooth, factory-correct power delivery and zero check-engine lights.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":50448277274872,"sku":"DS-EGVJT4KRW","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-xk8-2003-2006-4-2l-1.jpg?v=1788638184","url":"https:\/\/performancechiptuning.com\/fr\/products\/ignition-coil-and-iridium-spark-plugs-for-jaguar-xk8-2003-2006-4-2l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}