Mercedes-Benz CLK 350
Four-valve V6 with variable valve timing. Smooth and powerful. Known for balance shaft wear (revision sprocket) on early build years. Balance shaft gear problem addressed by Mercedes with a recall.
CLK 350: V6 at Its Best
200 kW M272 V6 in the CLK — coupé elegance meets a strong V6. Rare and desirable. The best non-AMG CLK experience.
Engine Weaknesses 6
The plastic balance shaft sprocket on the M272 wears prematurely from the timing chain. The right cylinder bank goes out of timing. Affected up to end of October 2006.
Symptoms: Fault codes P0016/P0017 (camshaft right bank), chain rattling, rough running at idle, in extreme cases engine damage
Alongside the balance shaft issue the M272 shows premature timing chain stretch. Chain wear on softer sprockets leads to timing deviations.
Symptoms: Chain noise especially on cold start, camshaft fault codes, rough running, engine irregularities
Four camshaft adjuster solenoids (two per cylinder bank) develop leaks; oil creeps into the wiring harness as far as the ECU. Repair costs up to €1,700 documented.
Symptoms: CEL, oil traces at camshaft connectors, lambda sensor failure due to oil contamination, non-specific faults that recur
Plastic components of the M272 variable intake system become brittle and break. The intake flap linkage snaps and sets fault code P2006.
Symptoms: Fault codes P2004/P2005/P2006 (intake flap), slight power loss, check engine light
The thermostat on the M272 preferentially fails in the open position. Operating temperature is not reached; especially on motorway runs temperature drops to 75–80°C.
Symptoms: Engine doesn't reach 90°C after 10–20 km, coolant temperature fluctuates heavily, reduced heater output, fault code P0128
The hydraulic engine mounts on the M272 lose their damping effect with age. Jerky movements are especially apparent when lifting off the throttle and during gear changes.
Symptoms: Vibrations in steering wheel and gear lever during load changes, judder on gear changes, droning at low revs
Vehicle Weaknesses 5
Valeo transmission oil heat exchanger on pre-facelift models up to 09/2003 develops leaks. Coolant enters the transmission and destroys the clutch packs. Symptom: humming and juddering at low revs.
Xenon headlight control modules and burners fail regularly after 1–2 years of operation. Third brake light breaks and fails frequently. Number plate lighting contacts corrode.
Brake caliper brackets corrode and cause rattling and squealing. Rear brake lines become brittle with age. Handbrake seizes when not used regularly.
COMMAND navigation system freezes or fails to start. Parktronic ultrasonic sensors fail regularly. CD changer jams. Seat belt retractor sticks.
The frameless side window drops when the door opens and rises when it closes. In frost the mechanism freezes; the door control module keeps trying to lower it — clicking in the module, flickering interior lighting.