Ignition Coil + Iridium Spark Plugs for Mercedes Benz CLS-Class (2012-2016) 4.7L 5.5L

Direct-Fit Ignition Coil and Iridium Spark Plug Kit for 2012-2016 Mercedes Benz CLS-Class 4.7L, 5.5L (C218 / M278, M157)

What it Does: The ignition coil and iridium spark plug kit replaces degraded factory ignition components on the 2012-2016 Mercedes Benz CLS-Class to eliminate high-boost misfires and restore precise combustion timing.

The Stock Mercedes Benz CLS-Class Secondary Breakdown Vulnerability

The twin-turbocharged M278 and M157 direct-injected engines in the C218 chassis generate extreme thermal loads inside the compact cylinder head valley. Over time, heat soak compromises the factory coil windings, degrading the internal copper windings and insulation boots. Concurrently, high cylinder pressures accelerate electrode erosion on standard plugs, expanding the spark gap. This dielectric stress induces spark blowout, high-rpm misfire codes, rough idle, and DME torque limiting under peak boost.

The Engineering Solution

This comprehensive service kit features eight heavy-duty coil packs and fine-wire double-iridium spark plugs engineered to withstand severe turbo duty cycles. The direct-fit ignition coils utilize high-dielectric epoxy potting and reinforced silicone boots to resist thermal degradation and current leakage. Matched with laser-welded iridium electrode spark plugs (OEM cross ZR6SII3320), this assembly maintains consistent spark energy under high cylinder pressure while resisting fouling and gap erosion.

Technical Specifications

Compatibility

• 2012-2016 Mercedes Benz CLS-Class CLS550 4.7L V8 Biturbo (M278)
• 2012-2014 Mercedes Benz CLS-Class CLS63 AMG 5.5L V8 Biturbo (M157)
• 2014-2016 Mercedes Benz CLS-Class CLS63 AMG S 5.5L V8 Biturbo (M157)

Frequently Asked Questions

Does this fit the C218 CLS-Class?
Yes, this is a direct fit for the 2012-2016 Mercedes Benz CLS-Class equipped with the M278 and M157 engine platforms.

Do these spark plugs require manual gapping before installation?
No, these double-iridium plugs are factory pre-gapped for direct application; altering the delicate fine-wire center electrode risks damage.

The Mercedes Benz Precision Standard

Direct-injection biturbo Mercedes-Benz engines demand exact electrical resistance tolerances to avoid triggering sensitive knock and misfire logic. This kit guarantees clean combustion delivery, restoring factory torque parameters and emissions compliance without throwing diagnostic trouble codes.