Ignition Coil and Iridium Spark Plugs for Mazda CX-9 (2007-2015) 3.5L 3.7L

Direct-Fit Ignition Coil and Iridium Spark Plug Kit for 2007-2015 Mazda CX-9

What it Does: Restores factory ignition energy and combustion efficiency across all six cylinders by replacing aged coils and worn plugs with high-dielectric coil-on-plug packs and fine-wire iridium spark plugs.

The Stock CX-9 Ignition Breakdown

The Ford-derived MZI V6 engine platform experiences thermal stress in transverse engine configurations, especially on the rear firewall cylinder bank. Over extended thermal cycling, factory coil epoxy degrades, leading to internal dielectric breakdown, micro-arcing, and intermittent primary winding resistance drift. Combined with premature electrode erosion on standard plugs, this causes low-RPM hesitation, erratic idle quality, cold-start misfires (P0300-P0306 DTCs), and unburned fuel dumping into catalytic converters.

The Engineering Solution

This direct-replacement kit uses high-grade copper internal windings shielded in thermal-resistant epoxy potting to eliminate internal shorting and voltage leakage under peak cylinder pressures. Paired with laser-welded iridium-tipped spark plugs, the assembly delivers a focused, high-energy spark kernel with reduced required firing voltage. Reinforced silicone boots and factory-spec blade terminals resist dielectric punch-through, ensuring sustained combustion stability under sustained load.

Technical Specifications

Compatibility

• 2007 Mazda CX-9 3.5L V6 (Sport, Touring, Grand Touring)
• 2008-2015 Mazda CX-9 3.7L V6 (Sport, Touring, Grand Touring)

The Mazda Reliability Standard

Engineered to eliminate check engine lights and maintain peak fuel atomization, this kit preserves the smooth power delivery, throttle response, and long-term drivetrain reliability expected from the TB-platform CX-9.