Mercedes-Benz GLK 200
Modern turbocharged four-cylinder with direct injection and piezo injectors. Successor to the M271. Less susceptible to timing chain issues. Good balance of power and economy.
Underpowered
Only 135 kW in the heavy SUV — the engine visibly struggles. Neither driving pleasure nor sovereign progress.
Engine Weaknesses 6
The high-pressure fuel pump on the M274 is driven by a lobe on the intake camshaft. Wear on the drive lobe or pump follower leads to pressure drop.
Symptoms: Metallic ticking from engine area, starting problems or extended cranking, power loss, fault code P0087
On the M274 too, the camshaft adjuster solenoids develop leaks. Oil penetrates the wiring harness by capillary action and can damage the engine ECU.
Symptoms: Fault code P0010, CEL, oil traces at camshaft connectors, lambda sensor failure, in severe cases ECU failure
Primary weak point of the M274: the electric thermostat sits deep in the engine block and is hard to reach. Replacement takes around 3 hours.
Symptoms: Engine does not reach operating temperature or overheats, temperature fluctuations, fault codes P0597–P0599
The PCV valve on the M274 clogs or breaks. Fault code P052E. Parts are inexpensive (~€63), but installed hidden under the engine ECU.
Symptoms: Fault code P052E, CEL, power loss, fault returns immediately after clearing
The M274 petrol engine has two NOx sensors that frequently fail. Each sensor costs around €600 as a part; with both sensors the repair bill quickly reaches €1,500.
Symptoms: Check engine light, NOx sensor fault code, elevated exhaust values, possible limp mode
The M274 with direct injection and no port injection tends to carbon deposits on intake valves like all GDI engines. Walnut blasting every 60,000–80,000 km is recommended.
Symptoms: Stumble under partial load, rough idle, slight power loss
Vehicle Weaknesses 7
OM642 diesel oil cooler tends to develop leaks at high mileage. Oil traces under the gearbox are a warning sign. Repair requires 7 hours of labour through complete disassembly.
Internal corrosion forms inside the hollow profile of the rear axle carrier behind the rubber mount. Structural integrity at risk with advanced infestation. Mercedes frequently covers repair under goodwill.
Brake lines corrode at line brackets where dirt and salt accumulate. Replacement requires lowering the rear axle, possibly also the fuel tank. Workshop costs 220–2,000 EUR.
Handbrake seizes when not used regularly. Brake lines corrode with age. Brake problems increase with vehicle age. Brake pads wear quickly on petrol models.
GLK is heavier than the related W204, resulting in higher wear on suspension bushings. Front control arm and anti-roll bar mounts particularly affected. Xenon headlight brackets vibrate.
Electric tailgate no longer opens fully or at all, control unit must be replaced. COMAND infotainment system freezes. Rear window wiper jams. Reversing camera fails sporadically.
Dirt accumulates under plastic covers and around retrofitted tow bars, leading to rust formation. Underbody in areas without regular inspection is susceptible.
Reports & Tests
944 owner complaints filed with NHTSA (2008–2015). Most reported: Airbags (648), Fuel System (75), Other (40).