Ignition Coil + Spark Plugs for Lincoln Navigator (2000-2004) 5.4L

High-Output Ignition Coil and Iridium Spark Plug Kit for 2000-2004 Lincoln Navigator (UN173 / U228)

What it Does: The ignition coil and iridium spark plug kit replaces worn factory ignition components on the 2000-2004 Lincoln Navigator to eliminate under-load misfires, restore combustion efficiency, and stabilize engine idle.

The Stock Lincoln Navigator Ignition Breakdown

Factory coil-on-plug (COP) units in the 5.4L InTech DOHC V8 are recessed deep within cylinder head wells, exposing them to extreme continuous heat soak and thermal cycling. Over time, the stock epoxy insulation develops micro-fractures and the rubber boots deteriorate, causing secondary voltage leakage, dielectric breakdown, and spark scatter. When paired with aged factory spark plugs exhibiting widened electrode gaps, the factory ignition system generates severe misfires, sluggish throttle response, and driveability hesitation under heavy towing loads.

The Engineering Solution

This complete ignition overhaul kit pairs heavy-duty coil packs with long-life iridium spark plugs to restore peak secondary circuit output. The replacement coils feature high-permeability magnetic cores, high-purity copper windings, and high-temp dielectric potting designed to withstand thermal saturation. Matched with fine-wire iridium center electrodes, the system lowers required firing voltage, provides a consistent flame kernel, resists carbon fouling, and supports dependable combustion under high-cylinder-pressure conditions.

What's Included

• 8 Performance Ignition Coils
• 8 Iridium Spark Plugs

Technical Specifications

Compatibility

• 2000-2004 Lincoln Navigator 5.4L V8

Frequently Asked Questions & Fitment Warnings

Does this fit the UN173 / U228 Navigator?

Yes, this is a direct fit for the 2000-2004 Lincoln Navigator equipped with the 5.4L InTech DOHC V8 engine. Confirm engine displacement and coil connector style prior to installation; not intended for universal or alternate engine applications.

Do I need to install new spark plug wires with this kit?

No, this application uses a direct Coil-on-Plug (COP) configuration with one coil per cylinder, so traditional spark plug wires are not used.

The Lincoln Durability Standard

Engineered to handle the demanding electrical loads of full-size towing and cross-country hauling, this ignition kit delivers reliable firing performance, balanced idle stability, and consistent torque output across all eight cylinders.