Ignition Coil + Spark Plugs for Mercedes Benz S-Class (2007-2011) 4.7L 5.5L

Direct-Fit Ignition Coil and Spark Plug Tune-Up Kit for 2007-2011 Mercedes Benz S-Class 4.7L, 5.5L (W221 / M273)

What it Does: The ignition coil and spark plug kit restores factory spark energy and cylinder combustion efficiency on the 2007-2011 Mercedes Benz S-Class to eliminate secondary ignition misfires, rough idle, and unburned fuel dumping.

The Stock Mercedes Benz S-Class Heat-Induced Breakdown

In the W221 engine bay, tightly packed packaging creates extreme thermal soak around the cylinder heads. Factory coils on the naturally aspirated M273 V8 suffer internal epoxy degradation, primary winding thermal breakdown, and dielectric boot dry-rotting over time. Simultaneously, factory spark plug electrode erosion widens the gap, increasing the secondary voltage demand required to jump the arc. This elevated electrical stress causes internal arcing inside fatigued coil packs, triggering P0300 through P0308 diagnostic trouble codes, cylinder deactivation limp modes, and accelerated catalytic converter fouling from unburnt hydrocarbons.

The Engineering Solution

This comprehensive tune-up kit replaces all eight coil packs and spark plugs simultaneously to balance secondary resistance across the entire firing order. The ignition coils utilize high-grade magnetic silicon steel cores with thermoset dielectric epoxy potting to resist thermal cycling and vibration. High-temperature silicone boots prevent flashover down the deep plug wells. Paired with fine-wire NGK LKR7BGP platinum-tipped spark plugs, this setup ensures low arc-strike voltage thresholds, sharp flame-kernel propagation, and consistent dwell-time performance up to high-RPM load conditions.

Technical Specifications

Compatibility

• 2007-2011 Mercedes-Benz S550 5.5L V8 (M273.961 / W221)
• 2007-2011 Mercedes-Benz S550 4MATIC 5.5L V8 (M273.968 / W221)
• 2008-2011 Mercedes-Benz S450 4MATIC 4.7L V8 (M273.924 / Canadian Market W221)

Frequently Asked Questions

Does this fit the W221 S-Class?
Yes, this is a direct fit for the 2007-2011 Mercedes Benz S-Class equipped with the naturally aspirated M273 V8 engine.

Should anti-seize compound be used during spark plug installation?
No, modern trivalent-plated NGK plug shells do not require anti-seize; apply factory torque specifications dry to prevent overtightening.

The Mercedes Benz Precision Standard

Maintaining the refined balance of the W221 chassis demands tight electrical tolerances. This direct-replacement coil-on-plug kit maintains exact Bosch ME 9.7 ECU dwell-angle calibration, ensuring zero check engine lights, smooth linear power delivery, and restored fuel economy across all driving profiles.