Ignition Coil and Iridium Spark Plugs for Jaguar S-Type (2003-2008) 4.2L

Direct-Replacement High-Dielectric Ignition Kit for 2003-2008 Jaguar S-Type

Primary Function: Restores factory spark energy and stabilizes combustion across all 8 cylinders by replacing worn coil-on-plug units and degraded spark plugs.

The Stock S-Type Thermal Ignition Degradation

The AJ-V8 engine bay packaging creates extreme thermal pockets around the cylinder heads. Over extended heat cycles, factory Jaguar coil boots suffer dielectric breakdown, and internal primary/secondary winding insulations crack. This causes micro-arcing, intermittent misfires under load, rough idle, and unburned fuel entering the catalytic converters, triggering persistent P0300-series trouble codes.

The Engineering Solution

This comprehensive ignition service kit features eight high-output coil-on-plug assemblies engineered with high-conductivity copper windings and heat-resistant epoxy potting to resist thermal saturation and voltage leakage. Paired with eight fine-wire iridium spark plugs, this setup reduces ignition voltage demand, optimizes flame front propagation, and provides consistent high-RPM spark delivery with durable blade terminals and OEM-matched connectors.

Technical Specifications

Compatibility

• 2003-2008 Jaguar S-Type 4.2L V8 (Naturally Aspirated)

The Jaguar Precision Standard

Engineered to meet European diagnostic tolerances, this matched 8-cylinder ignition pack prevents check-engine lights, eliminates hesitation under throttle tip-in, and restores refined luxury cruiser drivability.