{"product_id":"ignition-coil-and-iridium-spark-plugs-for-jaguar-xj8-1999-2003-4-0l","title":"Ignition Coil and Iridium Spark Plugs for Jaguar XJ8 (1999-2003) 4.0L","description":"\u003ch2\u003eDirect-Fit Ignition Coil and Iridium Spark Plug Kit for 1999-2003 Jaguar XJ8\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e Restores factory combustion efficiency and eliminates cylinder misfires by replacing degraded factory coil packs and worn plugs with high-dielectric coil-on-plug assemblies and fine-wire iridium spark plugs.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock XJ8 Secondary Ignition Degradation\u003c\/h3\u003e\n\u003cp\u003eThe Jaguar AJ-V8 engine positions ignition coils directly inside deep cylinder head wells sealed by engine beauty covers, subjecting the assemblies to extreme heat soak and thermal cycling. Over mileage, OEM coil insulation breaks down and rubber boots develop microscopic fissures, resulting in secondary voltage leakage to the head casting rather than the plug gap. This deterioration increases internal winding resistance, causing intermittent stumble, rough idle, and persistent P0300-P0308 diagnostic trouble codes under load.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis 8-cylinder ignition overhaul kit features heavy-duty coil-on-plug units engineered with high-conductivity copper windings and heat-resistant silicone boots to isolate spark delivery and prevent arc-over. Paired with eight laser-welded iridium spark plugs, the package reduces ignition voltage requirements, broadens flame kernel development, and resists electrode erosion. Direct-fit blade terminals ensure plug-and-play factory connector engagement without harness modification.\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;\"\u003e1999-2003 Jaguar XJ8\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;\"\u003e4.0L AJ27 V8 \/ X308\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 \/ 290 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;\"\u003eUF415, LNE1510AB, XW9312029AB, C1323, 5C1180\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1999 Jaguar XJ8 Base \/ L 4.0L V8\u003c\/li\u003e\n  \u003cli\u003e2000 Jaguar XJ8 Base \/ L 4.0L V8\u003c\/li\u003e\n  \u003cli\u003e2001 Jaguar XJ8 Base \/ L 4.0L V8\u003c\/li\u003e\n  \u003cli\u003e2002 Jaguar XJ8 Base \/ Sport 4.0L V8\u003c\/li\u003e\n  \u003cli\u003e2003 Jaguar XJ8 Base \/ Sport 4.0L V8\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eThe Jaguar Precision Standard\u003c\/h3\u003e\n\u003cp\u003eCalibrated to match factory European OBD-II dwell and resistance parameters, ensuring consistent spark energy, balanced idle stability, and zero false check engine lights across all operating temperatures.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":50447747514616,"sku":"DS-EV82U7FLP","price":175.95,"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-xj8-1999-2003-4-0l-1.jpg?v=1788622899","url":"https:\/\/performancechiptuning.com\/es\/products\/ignition-coil-and-iridium-spark-plugs-for-jaguar-xj8-1999-2003-4-0l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}