2007 Mercedes-Benz C350
The 2007 Mercedes-Benz C350 is a popular luxury sedan known for its blend of performance and comfort. The C-Class in 2007 also came with other engine options, including the C230 with a 2.5L V6 producing 201 hp and 181 lb-ft of torque, and the C280 with a 3.0L V6 that makes 228 hp and 221 lb-ft of torque. The C350 boasts a 3.5L V6 engine, delivering 268 horsepower and 258 lb-ft of torque. All engine options are paired with a 7-speed automatic transmission. Owners often appreciate the car’s elegant styling, refined interior, and spirited driving dynamics. Common criticisms include higher maintenance costs and some reliability concerns.
Engine
3.5L V6 (M272)
- Camshaft Adjuster (Magnet) Failure
- Description/Symptoms: The camshaft adjuster magnets, which control variable valve timing, can fail, causing the check engine light to illuminate. Diagnostic Trouble Codes (DTCs) P0016 and P0017 are often associated with this issue. Rough idling and decreased performance may also be observed.
- Solution: Replacement of the faulty camshaft adjuster magnet(s). It is advisable to replace all four if one fails to prevent future problems.
- Estimated Cost to Fix: $200 - $600+
- Recalls: None Found
- Balance Shaft Sprocket Wear
- Description/Symptoms: This is a well-documented issue affecting certain M272 engines produced within a specific date range. Premature wear of the balance shaft sprocket can lead to significant engine problems. Symptoms may include a check engine light, rough running, and eventual engine failure if not addressed. The issue is not always noticeable until it becomes severe.
- Solution: Replacement of the balance shaft. This is a labor-intensive repair.
- Estimated Cost to Fix: $2,500 - $5,000+
- Recalls: None Found
- Intake Manifold Runner Flap Failure
- Description/Symptoms: The plastic intake manifold can develop cracks and the internal runner flaps can break, causing air leaks and poor engine performance. A check engine light is usually present with codes related to intake manifold performance.
- Solution: Replacement of the entire intake manifold assembly.
- Estimated Cost to Fix: $800 - $1,500+
- Recalls: None Found
Transmission
7G-Tronic (722.9)
- Valve Body Issues
- Description/Symptoms: The 7G-Tronic transmission (722.9) can experience valve body problems, leading to harsh or delayed shifting, erratic gear selection, and getting stuck in gear (limp mode). These issues can be intermittent.
- Solution: Replacement or rebuild of the valve body. In some cases, the entire transmission may need replacement if the problem is severe.
- Estimated Cost to Fix: $800 - $3,000+
- Recalls: None Found
- Torque Converter Failure
- Description/Symptoms: Shuddering, slipping, or unusual noises coming from the transmission, especially at lower speeds.
- Solution: Replacement of the torque converter, along with a transmission flush.
- Estimated Cost to Fix: $1,500 - $3,000+
- Recalls: None Found
Suspension
- Front Control Arm Bushing Failure
- Description/Symptoms: Premature wear and cracking of the front control arm bushings. This can result in clunking noises from the front suspension, especially when going over bumps, as well as vague steering and uneven tire wear.
- Solution: Replacement of the front control arms or just the bushings, although replacing the entire control arm is generally recommended.
- Estimated Cost to Fix: $400 - $1,000+
- Recalls: None Found
Electrical
- EIS (Electronic Ignition Switch) Failure
- Description/Symptoms: The EIS can fail, preventing the key from being recognized, and thus the car will not start. This is a common problem with these models.
- Solution: Replacement of the EIS and reprogramming. This often requires specialized equipment and expertise.
- Estimated Cost to Fix: $800 - $1,500+
- Recalls: None Found
- SAM (Signal Acquisition Module) Failure
- Description/Symptoms: SAM units control various electrical functions and are prone to failure due to water intrusion or electrical surges. Symptoms can include malfunctioning lights, wipers, locks, or other electrical components.
- Solution: Replacement of the faulty SAM unit and reprogramming.
- Estimated Cost to Fix: $500 - $1,200+
- Recalls: None Found
Exterior
- Rust
- Description/Symptoms: Rust on the fender wells, door seams, and around the wheel wells
- Solution: Cut out the existing rust, weld in new metal, repaint
- Estimated Cost to Fix: $500 - $3,000+
- Recalls: None Found
Interior
- Sunroof Issues
- Description/Symptoms: The sunroof can malfunction, becoming stuck open or closed, or making excessive noise during operation. The mechanism is known to be fragile.
- Solution: Repair or replacement of the sunroof mechanism.
- Estimated Cost to Fix: $300 - $1,000+
- Recalls: None Found
- Command Center Screen Failure
- Description/Symptoms: The screen begins to fade, show lines, or not come on at all.
- Solution: Replacement of the screen
- Estimated Cost to Fix: $500 - $2,000+
- Recalls: None Found
Summary
The 2007 Mercedes-Benz C350 presents a mixed bag of potential issues. While the engine offers good performance, problems like balance shaft wear and camshaft adjuster failures can lead to expensive repairs. Transmission issues, particularly with the valve body, are also relatively common. Electrical problems, especially with the EIS and SAM units, can be frustrating. Suspension and interior issues, while less severe, can still contribute to overall ownership costs. Potential buyers should be aware of these common problems and factor them into their purchase decision. A pre-purchase inspection by a qualified mechanic is highly recommended. The severity of these problems ranges from minor electrical glitches to major engine and transmission overhauls, with repair costs varying accordingly.