Ignition Coil and Iridium Spark Plugs for Chrysler 300M (1998-2004) 3.5L

Direct-Replacement Ignition Coil and Iridium Spark Plug Kit for 1998-2004 Chrysler 300M

What it Does: The ignition coil and iridium spark plug kit replaces aged factory ignition components on the 1998-2004 Chrysler 300M to eliminate cylinder misfires, stabilize idle, and restore peak combustion efficiency.

The Stock Chrysler 300M Secondary Ignition Breakdown

On the LH platform, the factory 3.5L EGG V6 exposes its pencil ignition coils to severe thermal cycling within deep spark plug wells. Over time, engine bay heat soak degrades the internal primary and secondary copper windings, while thermal fatigue breaks down the silicone dielectric boots. This deterioration causes micro-arcing, carbon tracking, and intermittent misfires (often triggering DTCs P0300 through P0306) under heavy throttle. Concurrently, factory copper or standard platinum plugs suffer electrode erosion, widening the spark gap and forcing aged coils to output unsustainable secondary voltages, eventually leading to coil driver stress in the powertrain control module (PCM).

The Engineering Solution

This direct-fit overhaul kit provides six high-dielectric pencil ignition coils engineered with high-conductivity copper windings and reinforced epoxy potting to resist thermal shock and voltage leakage. Paired with six fine-wire iridium spark plugs, the setup minimizes quenching and substantially lowers the required ignition voltage compared to conventional designs. The laser-welded iridium center electrodes maintain tight spark gaps across thousands of heat cycles, ensuring complete flame-front propagation under high cylinder pressures and curing cold-start stumbling.

Technical Specifications

Compatibility

• 1998-2004 Chrysler 300M Base Sedan 3.5L V6 (EGG)
• 2002-2004 Chrysler 300M Special Sedan 3.5L V6 (EGG High Output)

Frequently Asked Questions

Does this fit the LH 300M?
Yes, this is a direct fit for the 1998-2004 Chrysler 300M equipped with the 3.5L EGG engine.

Do the included iridium spark plugs require manual gapping before installation?
No, the iridium spark plugs come pre-gapped to factory specifications, and manual adjustment is discouraged to prevent damaging the fine-wire iridium electrode tip.

The Chrysler Touring Caliber

The cab-forward Chrysler LH-body demands reliable ignition timing to sustain its balance of highway cruising power and smooth power delivery. Refreshing the secondary ignition restores effortless V6 throttle response and consistent fuel economy across long hauls.