Ignition Coil + Iridium Spark Plugs for Mercedes Benz M-Class (2012-2015) 4.7L 5.5L

Direct-Fit OEM-Spec Ignition Coil & Iridium Spark Plug Kit for 2012-2015 Mercedes Benz M-Class 4.7L, 5.5L (W166 / M278, M157)

What it Does: The Ignition Coil + Iridium Spark Plug Kit replaces worn factory ignition components on the 2012-2015 Mercedes Benz M-Class to eliminate high-boost misfires and restore combustion efficiency.

The Stock Mercedes Benz M-Class Ignition Degradation

Under the high cylinder pressures of the twin-turbocharged M278 and M157 engines, factory ignition systems experience severe thermal cycling. The enclosed packaging of the W166 engine bay leads to chronic heat soak, breaking down the internal epoxy insulation and primary/secondary windings of factory coils. Over time, this degradation causes internal micro-arcing and spark blowout under load. Simultaneously, standard plug electrodes suffer gap erosion from sustained high combustion temperatures, widening the gap and forcing the coil to operate at maximum dielectric stress, ultimately triggering P0300-series multi-cylinder misfire fault codes.

The Engineering Solution

This refresh package delivers eight direct-fit coil-on-plug units engineered to meet or exceed OEM dielectric resilience alongside matched Bosch fine-wire double-iridium spark plugs. Designed to replace OE part numbers A2769063700 and 2769060501, the ignition coils feature heat-resistant thermoplastic housings and premium magnetic core laminations that provide consistent secondary voltage under peak boost. Paired with laser-welded iridium center electrodes, this kit reduces voltage demand, stabilizes idle quality, resists fouling, and delivers rapid spark discharge for complete flame front propagation across the entire RPM band.

Technical Specifications

Compatibility

• 2012-2014 Mercedes Benz M-Class ML550 4.7L V8 Biturbo (M278)
• 2012-2015 Mercedes Benz M-Class ML63 AMG 5.5L V8 Biturbo (M157)

Frequently Asked Questions

Does this fit the W166 M-Class?
Yes, this is a direct fit for the 2012-2015 Mercedes Benz M-Class equipped with the M278 or M157 engine.

Do these spark plugs require pre-gapping before installation?
No, these double-iridium plugs are factory pre-gapped for direct-injection biturbo V8 applications and should be torqued to OEM specifications without altering the delicate fine-wire gap.

The Mercedes Benz Precision Standard

Engineered for high-output European biturbo powertrains, these ignition components ensure exact electrical continuity, zero check-engine lights, and clean high-RPM combustion execution under demanding load profiles.