2009 Mercedes-Benz C350 Problem Reports
Newest 2009 Mercedes-Benz C350 Problem Reports
The mass air flow sensor tends to fail causing poor fuel economy and Check Engine light illumination. The engine air filter should be replaced when the mass air flow sensor is replaced; a dirty filter can allow debris to damage the new sensor.
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.
The camshaft adjuster solenoid (which is related to the variable valve timing system) may fail or timing chain/balance shaft components may wear, resulting in illumination of the Check Engine Light and various drivability issues. Mercedes-Benz has released a service bulletin outlining specific repair instructions depending on fault codes stored.
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.
Irregular and premature tire wear can be caused by the front thrust link bushings cracking and causing excessive movement in the suspension. The thrust link bushings are fluid-filled (to help reduce vibration), so if they crack, they will leak oil.
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.
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.
Vehicles equipped with a 7-speed automatic transmission may develop a rough shifting condition, most commonly going up from first to second gear and going down from third to second or second to first gear. Our technicians tell us this is due to an internal component failure. Mercedes has released updated parts; the transmission will need to be removed and disassembled to complete the necessary repairs.
Inside grab handles, the upholstery on the center console cover, and door trim panels can delaminate. Most commonly replacement of the affected part is necessary.
Due to the size and material used on the brakes of these vehicles, the brakes may start to squeak around the 50 percent wear point. The brake rotor surfaces become uneven, causing a lip to form at the outer edge of the rotor. Because of this, the rotors are usually replaced when the pads are worn (pad life varies depending on driving style and terrain).
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.
High mileage or older vehicles commonly develop leaks from the differential seals and/or cover. Our technicians recommend a complete reseal of the differential unit whenever these leaks are repaired.
The SRS (airbag) light can come on if liquids are spilled into the seat belt buckles, or if the liquid pools underneath the seat and gets into the electrical connector for the seat belt pretensioner. Damaged components will require replacement to restore proper airbag operation.