Ignition Coil and Iridium Spark Plugs for Cadillac XLR (2006-2009) 4.4L

High-Dielectric Ignition Coil and Iridium Spark Plug Service Kit for 2006-2009 Cadillac XLR

Direct-fit 8-cylinder ignition overhaul kit: Restores high-rpm spark energy, eliminates boost-induced misfires, and stabilizes idle across supercharged Northstar applications.

The Stock XLR-V Thermal Breakdown and Spark Blowout

The supercharged 4.4L LC3 engine operates in a tightly packaged, high-heat engine bay that accelerates dielectric fatigue in factory ignition coil insulation. Over time, extreme thermal cycling degrades internal epoxy potting and secondary copper windings, producing micro-arcing and intermittent secondary circuit resistance. Coupled with eroded factory plug gaps under positive manifold pressure, this degradation leads to high-load spark blowout, hesitation, erratic idle stability, and diagnostic trouble codes such as P0300 through P0308.

The Engineering Solution

This comprehensive ignition pack pairs heavy-duty coil-on-plug assemblies with fine-wire iridium spark plugs to handle high cylinder pressures. The coils feature reinforced thermoplastic housings, high-purity copper primary and secondary windings, and high-temp silicone boots that isolate secondary voltages exceeding 35kV. The matched iridium plugs utilize a laser-welded fine-wire center electrode and high-alumina ceramic insulator, reducing required firing voltage, providing exceptional thermal conductivity, and guaranteeing sharp combustion timing under boost.

Technical Specifications

Compatibility

• 2006 Cadillac XLR: 4.4L V8 Supercharged (LC3 / V-Series)
• 2007 Cadillac XLR: 4.4L V8 Supercharged (LC3 / V-Series)
• 2008 Cadillac XLR: 4.4L V8 Supercharged (LC3 / V-Series)
• 2009 Cadillac XLR: 4.4L V8 Supercharged (LC3 / V-Series)

The Cadillac Precision Benchmark

Engineered to meet the tight tolerances of forced-induction luxury roadsters, this complete ignition refresh provides exact plug-and-play OE terminal alignment, instant throttle response, and consistent multi-strike combustion without triggering false misfire codes.