Ignition Coil & Iridium Spark Plugs & Wire for Isuzu Ascender (2003-2004) 5.3L

Direct-Fit Ignition Coil, Wire, and Iridium Plug Service Kit for 2003-2004 Isuzu Ascender

What it Does: Restores lost spark energy, stabilizes idle, and eliminates secondary ignition misfires across all eight cylinders under heavy load.

The Stock Ascender Ignition Breakdown

Factory coil packs on the GMT370 platform suffer from severe thermal cycling and moisture intrusion over time. Located tightly along the valve covers directly above exhaust manifolds, OEM round coils develop micro-cracks in their epoxy encapsulation, causing internal dielectric breakdown. Concurrently, factory carbon-core plug wires degrade internally from persistent heat soak, causing high conductor resistance, weak spark delivery, intermittent P0300 misfire codes, and degraded towing performance.

The Engineering Solution

This comprehensive overhaul kit features heavy-duty round-style (UF262/D585) coil-on-plug packs sealed with premium high-dielectric epoxy and high-temp silicone boots to prevent voltage arcing. Matched with 8mm red silicone-jacketed plug wires containing stranded copper cores and stainless heat-shielded terminals, this assembly minimizes electrical resistance. Pre-gapped iridium-tipped spark plugs offer superior thermal conductance and a fine-wire electrode design that resists carbon fouling under high combustion pressures.

Technical Specifications

Compatibility

• 2003 Isuzu Ascender Base 5.3L V8 (Round UF262 / D585 Coils)
• 2003 Isuzu Ascender Limited 5.3L V8 (Round UF262 / D585 Coils)
• 2003 Isuzu Ascender LS 5.3L V8 (Round UF262 / D585 Coils)
• 2004 Isuzu Ascender Limited 5.3L V8 (Round UF262 / D585 Coils)
• 2004 Isuzu Ascender LS 5.3L V8 (Round UF262 / D585 Coils)
• 2004 Isuzu Ascender S 5.3L V8 (Round UF262 / D585 Coils)

The Isuzu Heavy-Duty Standard

Engineered to withstand the sustained cylinder pressures and elevated thermal loads of heavy towing and off-highway duty, this ignition package delivers consistent, high-energy combustion without voltage drop or hesitation.