Ignition Coil + Iridium Spark Plugs for Mercedes Benz CL-Class (2011-2014) 4.7L 5.5L

OEM-Grade Ignition Coil and Iridium Spark Plug Kit for 2011-2014 Mercedes Benz CL-Class 4.7L, 5.5L (C216 M278 / M157)

What it Does: The complete ignition kit replaces worn coil-on-plug modules and fouled plugs on the 2011-2014 Mercedes Benz CL-Class to eliminate high-boost misfires, restore clean flame kernel development, and stabilize idle quality.

The Stock Mercedes Benz CL-Class Thermal Breakdown

In the C216 chassis, the twin-turbocharged M278 and M157 engines generate extreme underhood thermal loads. Prolonged heat soak severely degrades factory coil epoxy insulation, causing internal dielectric breakdown, micro-arcing, and intermittent primary winding failure. Simultaneously, extreme cylinder pressures inherent to direct-injected biturbo applications erode standard plug gaps, leading to severe spark blow-out and rough running under load.

The Engineering Solution

This service kit resolves secondary ignition loss by matching 8 high-output direct-replacement ignition coils with factory-matched Bosch double iridium spark plugs. Engineered with high-dielectric internal epoxy and reinforced silicone boots, these coils resist voltage leakage under peak cylinder pressures. The pre-gapped Bosch ZR6SII3320 double iridium plugs utilize a laser-welded fine-wire center electrode and platinum ground inlay to maintain precise arc gap tolerances, prevent heat-induced fouling, and ensure stable combustion.

Technical Specifications

Compatibility

• 2011-2014 Mercedes Benz CL-Class CL550 4.7L V8 Biturbo (M278)
• 2011-2014 Mercedes Benz CL-Class CL63 AMG 5.5L V8 Biturbo (M157)

Frequently Asked Questions

Does this fit the C216 CL-Class?
Yes, this is a direct fit for the 2011-2014 Mercedes Benz CL-Class equipped with the M278 4.7L or M157 5.5L Biturbo V8 engines.

What is the recommended installation torque for the spark plugs?
Torque the plugs dry to the factory-specified 23 Nm (17 lb-ft) into cold aluminum cylinder heads to maintain proper ground electrode indexing.

The Mercedes Benz Precision Standard

Maintaining European high-output powertrains demands strict adherence to OE electrical impedance and ignition timing parameters. This direct-replacement kit delivers precise secondary voltage output that interfaces seamlessly with the Bosch MED17.7 ECU, eliminating phantom misfire fault codes and preserving catalytic converter efficiency.