The M282 four-cylinder engine family—found across the A-Class, CLA, and GLA lineup—has proven efficient, but its coil-on-plug design has become a recurring service item as these cars age past 60,000 miles. Owners report misfire codes (P0301 through P0304) and rough cold starts, often traced back to the original coil packs developing micro-cracks in their epoxy housings. That’s where the aftermarket is stepping in with updated designs, including the OSRAM OS1308 unit built to supersede the factory A2829060000 part.
Key Specs: OSRAM OS1308 Ignition Coil
- Type: Coil-on-plug (COP), pencil-style
- OE Cross-Reference: A2829060000 / 224332935R
- Compatibility: 3 Mercedes-Benz applications (M282 engine)
- Construction: Epoxy-sealed housing, brass secondary terminal
- Output: Matches OEM spark energy curve for M282 calibration
Why the OEM Coil Fails Earlier Than It Should
The factory coil on the M282 is a compact unit, packed tight between the valve cover and the intake manifold. Heat soak from the turbocharger—mounted directly behind the engine—accelerates thermal cycling on the coil’s internal insulation. Over time, the secondary winding’s varnish degrades, and the coil starts bleeding voltage to ground instead of firing the plug. The result is a soft misfire under load that often doesn’t trigger a check-engine light until it’s severe.
What’s interesting is that this failure mode is well-documented on Mercedes forums, yet the OEM replacement cost still runs $80–$120 per coil at the dealer. For a four-cylinder, that’s a $400+ repair before labor. The aftermarket has responded with coils like the OS1308 that use a thicker epoxy compound and a redesigned bobbin to handle the thermal load better, at roughly half the dealer price.
Spark Energy vs. Fuel Economy: What Actually Changes
When you upgrade from a worn OEM coil to a fresh performance-grade unit, the immediate benefit isn’t more horsepower—it’s more complete combustion. A coil that delivers consistent spark energy across the RPM range ensures the air-fuel mixture ignites fully, reducing unburnt fuel that would otherwise be dumped into the catalytic converter. On the M282, that translates to:
- Smoother idle (especially on cold starts)
- Recovered fuel economy (typically 2–4% if the old coil was misfiring intermittently)
- Fewer false lean codes from oxygen sensors reading raw fuel in the exhaust
The OSRAM coil doesn’t claim to boost voltage beyond OEM specs—and you don’t want it to. The M282’s engine control unit expects a specific spark duration and current draw. A hotter “performance” coil can overheat the ignition driver in the ECU, causing long-term damage. The smart upgrade is a coil that matches OEM spark energy but does so more reliably over time.
The Verdict for Mercedes Owners
If you’re already chasing a misfire on your M282-powered Mercedes, replace all four coils at once—not just the failed cylinder. Mixing an old coil with new ones will cause uneven spark energy and can trigger a cascade of misfires within a few thousand miles. The OS1308 | OSRAM Ignition Coil | Fits Mercedes-Benz | OE# A2829060000 224332935R is a direct-fit replacement that addresses the known heat-related failure point, making it a solid choice for DIYers and shops alike.
For enthusiasts considering a true performance ignition upgrade—higher voltage, multi-spark CDI systems—save your money. The M282’s ECU isn’t programmed to benefit from it, and you risk drivability issues. Stick with a quality OEM-spec coil, keep your spark plugs fresh (NGK or Bosch, OEM gap), and the ignition system will outlast the rest of the car.
OS1308 | OSRAM Ignition Coil | Fits Mercedes-Benz | OE# A2829060000 224332935R is worth a look if you’re replacing coils this season. It fits the 3 most common M282 applications and ships with the same connector and mounting bracket as the factory unit—no adapters, no wiring changes. That’s the kind of straightforward replacement you want when the car’s already on the lift.
Recommended Part: OS1308 – OE-grade replacement, in stock now.
