Ignition Coil and Iridium Spark Plugs for Hyundai XG350 (2003-2005) 3.5L

Direct-Fit Ignition Coil and Iridium Spark Plug Kit for 2003-2005 Hyundai XG350

What it Does: The Ignition Coil and Iridium Spark Plug Kit restores secondary ignition voltage and combustion efficiency on the 2003-2005 Hyundai XG350 to eliminate cylinder misfires, stabilize erratic idle, and restore lost engine power.

The Stock Hyundai XG350 Ignition Breakdown

On the XG chassis equipped with the 3.5L Sigma G6CU V6, the factory waste-spark ignition configuration subjects the three bank-mounted coils to severe thermal degradation beneath the engine acoustic cover. Over prolonged run times, excessive heat soak deteriorates the internal epoxy potting and breakdown occurs across the copper primary and secondary windings. As internal insulation degrades, dielectric breakdown causes spark energy leakage and micro-arcing. Compounded by widened gaps on worn factory spark plugs, the elevated voltage demand overburdens the coils, triggering P0300-series misfire diagnostic trouble codes, poor throttle response, and incomplete fuel burn that risks catalyst contamination.

The Engineering Solution

This comprehensive refresh kit replaces failing components with three high-dielectric pencil ignition coils and six fine-wire iridium spark plugs engineered to withstand aggressive thermal cycling. The replacement coils utilize reinforced thermoplastic housings filled with high-grade polyurethane epoxy to insulate against voltage punch-through and resist vibrational stress. Paired with laser-welded fine-wire iridium center electrodes, the system significantly lowers the required firing voltage while generating a hotter, more concentrated spark kernel. This waste-spark matched setup prevents carbon fouling, stabilizes secondary circuit impedance, and ensures complete combustion under high engine load without premature gap erosion.

Technical Specifications

Compatibility

• 2003 Hyundai XG350 Base 3.5L V6 (G6CU)
• 2003 Hyundai XG350 L 3.5L V6 (G6CU)
• 2004 Hyundai XG350 Base 3.5L V6 (G6CU)
• 2004 Hyundai XG350 L 3.5L V6 (G6CU)
• 2005 Hyundai XG350 Base 3.5L V6 (G6CU)
• 2005 Hyundai XG350 L 3.5L V6 (G6CU)

Frequently Asked Questions

Does this fit the XG XG350?
Yes, this is a direct fit for the 2003-2005 Hyundai XG350 equipped with the Sigma G6CU engine.

Why are there only three coils included for a six-cylinder engine?
The 3.5L Sigma G6CU utilizes a waste-spark ignition arrangement where three primary coils each fire two cylinders simultaneously.

The Hyundai Executive Sedan Standard

Engineered to meet original equipment tolerance thresholds, this ignition overhaul ensures smooth power delivery, clean emissions, and dependable highway cruising without recurring check engine lights.