Vehicles using M254.920 engine list:

Engine M254.920

Symptoms:
- Rough idling or misfires during acceleration
- Loss of power or hesitation under load
- Check Engine Light (CEL) illumination
- Unusual engine noises such as ticking or knocking
- Increased oil consumption or visible leaks

Diagnosis:
- Perform a thorough OBD-II scan to identify fault codes related to ignition coils, fuel injectors, or camshaft sensors.
- Inspect ignition coils and spark plugs for wear or damage, as these are common failure points.
- Check for vacuum leaks or intake manifold gasket issues that can cause rough running.
- Examine the turbocharger system for boost leaks or malfunctioning wastegate actuators.
- Assess oil quality and level to rule out lubrication-related problems.
- Verify software updates and engine control unit (ECU) calibrations are current to prevent known issues.

Fixes:
- Replace faulty ignition coils or spark plugs to restore proper combustion.
- Repair or replace leaking intake manifold gaskets or vacuum lines.
- Service or replace turbocharger components if boost pressure is inadequate.
- Address oil leaks by replacing seals or gaskets as needed.
- Update ECU software to the latest version provided by Mercedes-Benz to improve engine management and reliability.
- Perform regular oil and filter changes using manufacturer-recommended specifications to maintain engine health.

Prevention:
- Adhere strictly to the scheduled maintenance intervals outlined by Mercedes-Benz, including oil changes and spark plug replacements.
- Use only approved engine oils and high-quality fuel to minimize deposit formation and wear.
- Monitor engine performance regularly and address any warning signs promptly to avoid escalation.
- Keep software and firmware updated through authorized service centers.
- Avoid extended idling and aggressive driving to reduce stress on engine components.
- Ensure cooling system is functioning properly to prevent overheating and related engine damage.

Following these guidelines helps maintain the M254.920 engine’s performance and longevity across the specified Mercedes-Benz models.