Engine Camshaft Position Sensor Guide for 2007-2017 Mercedes-Benz S550
Understanding and resolving camshaft position sensor issues in your S550 to maintain engine performance and prevent costly repairs.
- Your S550 has four camshaft position sensors; it is recommended to replace all four at the same time.
- A major known issue is oil leaking through the sensor into the wiring harness, which can destroy the ECU. Inspect connectors for oil.
- This is an easy DIY repair that can be completed in about an hour with basic tools.
- Choose high-quality aftermarket brands like Bosch, Hella, or Delphi for reliability that is close to OEM standards.
Is Your S550 Camshaft Position Sensor Failing?
A failing camshaft position sensor in a 2007-2017 Mercedes-Benz S550 can cause a range of noticeable engine problems. The most common sign is the Check Engine Light illuminating on your dashboard. You might also experience drivability issues like engine hesitation, rough idling, stalling, or a general lack of power. 🎬 See how to diagnose common camshaft sensor fault codes. In some cases, the car may take a long time to start or fail to start at all. These symptoms often start small but can worsen, potentially leaving you stranded.
A Common and Critical S550 Issue: Oil Leaks
A widely documented problem for the M273 and M278 engines in the S550 is oil leaking through the camshaft position sensor's body. The internal seals of the sensor fail, allowing pressurized engine oil to seep into the electrical connector. From there, by a process called capillary action, the oil can travel down the entire length of the engine wiring harness, eventually contaminating the main engine computer (ECU). 🎬 Watch this warning about oil leaking into your wiring harness. This can lead to misfires, strange electrical behavior, and ultimately, a very expensive repair involving the replacement of the sensors, wiring harness, and ECU. Regularly inspecting the sensor connectors for oil is a critical preventative maintenance step.
Choosing the Right Aftermarket Sensor
When replacing a camshaft position sensor on a high-performance vehicle like the S550, part quality is crucial. While OEM parts are an option, several aftermarket brands offer reliable alternatives at a better price. They can be grouped into tiers based on quality and reputation among Mercedes owners.
Brand Quality Tiers
- Tier 1 (OEM / OE-Equivalent): Brands like Bosch and Hella are often the original equipment manufacturers for Mercedes-Benz. Choosing these brands is the closest you can get to buying a part from the dealer without the high markup. They are engineered to the exact specifications of your vehicle.
- Tier 2 (Reputable Aftermarket): Brands such as Delphi, Vemo, and Standard Ignition (SMP) have a strong reputation for producing quality electronic components. They offer a balance of reliability and value, making them a solid choice for most owners.
- Tier 3 (Value Brands): This category includes brands like Walker Products, Holstein, and others that focus on affordability. While they can be a budget-friendly solution, for a critical sensor on an S550, it's often wiser to invest in a Tier 1 or Tier 2 brand to avoid premature failure and potential engine issues.
Pro Tip: Replace in Sets and Check for Oil
Because all four sensors are the same age, it's wise to replace them all at once if one fails, especially if you have a higher-mileage vehicle. This prevents you from having to repeat the repair in the near future. When replacing, always clean the sensor connectors with electrical contact cleaner and inspect for any signs of oil contamination in the harness.
Cost to Replace S550 Camshaft Position Sensors
The cost can vary depending on the parts you choose and whether you perform the labor yourself. The job is considered easy for a DIYer.
| Part/Service | Estimated Cost |
|---|---|
| New OEM Sensor (per sensor) | $90 - $150 |
| New Aftermarket Sensor (per sensor) | $22 - $97 |
| Shop Labor (for all four) | $100 - $200 |
Frequently Asked Questions
How many camshaft position sensors does my S550 have?
Your 2007-2017 S550, with either the M273 or M278 V8 engine, has four camshafts (two intake, two exhaust) and therefore has four camshaft position sensors located at the front of the engine.
Is this a difficult DIY repair?
No, this is a very feasible DIY repair. Each sensor is held by a single T30 Torx bolt and has a simple electrical connector. The main challenge is accessing the sensors, which may require removing the engine air intake ducts. The entire job for all four sensors can typically be done in under an hour.
🎬 Follow this step-by-step guide to replace your S550 sensors.What happens if I ignore a bad camshaft sensor?
Ignoring the symptoms can lead to worsening performance, poor fuel economy, and eventually a no-start condition. For the S550 specifically, ignoring a sensor that is leaking oil can lead to catastrophic failure of the engine wiring harness and ECU, a repair that can cost thousands of dollars.
Are there any recalls for this issue?
There are no specific recalls for the camshaft position sensor itself on the 2007-2017 S550. However, the issue of oil leaking through the sensors and into the wiring harness is a well-known problem across many Mercedes-Benz models with these engines.
Helpful Videos
Technical Specifications
OEM Part Numbers: 2769051000 A2769051000
The S550 uses four identical 3-pin Hall-effect sensors. They are located on the front of the cylinder heads. The replacement procedure typically requires a T30 Torx bit.
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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Mercedes-Benz S550:
- 🎬 Helpful Videos
- 🛍️ Shop This Part
- Is Your S550 Camshaft Position Sensor Failing?
- A Common and Critical S550 Issue: Oil Leaks
- Choosing the Right Aftermarket Sensor
- Brand Quality Tiers
- Pro Tip: Replace in Sets and Check for Oil
- Cost to Replace S550 Camshaft Position Sensors
- Frequently Asked Questions
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