Failed spark plug wires and/or ignition coils can cause intermittent misfires (rough running); the Check Engine Light may also illuminate. Diagnoses of the ignition system will be necessary to determine which components are at fault.
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Newest reported 2003 Mercedes-Benz CLK500 problems
The crankshaft position sensor may fail. Symptoms of this are: The engine will crank—but not start—especially when the engine is warm. The car may start again if it is left to cool off, but it may run roughly or have poor performance. Communicating these specific symptoms to your technician can save diagnostic time.
Computer control modules for the seats and doors, the CD changer, and the brake lamp switch tend to fail.
The heating, ventilation and AC (HVAC) heater box is susceptible to mildew buildup. This can result in a musty odor from the HVAC system, most noticeable when the system is first turned on.
Going over large bumps in convertible models may cause the roll bar to deploy, rendering the roof inoperative. Special tools are generally required to return the roll bar to its stowed position.
An engine Oil leak may develop from the PCV vent housing on the valve cover and/or the inspection plate on the front of the engine.
The rubber bond in the harmonic balancer can decay, which causes the balancer to move and work its way toward the timing cover. If the balancer comes into contact with the timing cover while the engine is running, it will fracture and damage the cover and potentially other surrounding parts. The harmonic balancer should be inspected at every service.
The electrical connector at the automatic transmission may leak fluid into the wiring harness. If not repaired, the oil will migrate through the wiring harness and damage the transmission control module. At that point, a new harness and control module may be necessary to correct this problem.
Torque thrust bushings in the front suspension may crack and leak oil, this causes steering alignment problems and excessive tire wear. Another symptom of a worn bushing is a clunk or thud noted when turning, on hard acceleration, or hard braking.
A repetitive clicking noise from behind the center area of the dash panel is usually caused by a broken stepper motor actuating arm. The actuating arm controls the direction of air flow in the climate control system. Disassembly of the center console will be required to access and change the broken arm with the updated, reinforced part.
The sway bar end link joints may wear and cause a knocking noise over bumps. Loose or warn links should be replaced to correct this type of noise.
Cup holders in the dash are known to break requiring repair or replacement.