One issue commonly experienced by Mercedes owners is the failure of the crankshaft position sensor, popularly called CPS. Problems with CPS are fairly common, but most of the time go unnoticed for some time.
The crankshaft position sensor is attached to the engine block facing the timing rotor on the engine crankshaft. The sensor picks up signals used by the engine electronic control unit to calculate the crankshaft position and the engine rotational speed.
In short, it’s job is to monitor the engine’s many moving parts, including the crankshaft, engine valves and pistons. It relays information to the vehicle’s computer, referencing how fast the vehicle is running as well as the position of the crankshaft and the cylinder. The sensor is crucial in controlling ignition and timing of the engine as well as the injection of fuel into the engine for combustion. The failure of the CPS is usually caused by a few problems which shall be discussed below.
Causes of Crankshaft Position Sensor Failure
The following are common causes of CPS failure in a Mercedes:
- Excessive Heat: A common cause of a faulty crankshaft position sensor is excessive heat. Excessive heat can cause several problems in an engine. If the car’s engine is producing excessive heat as a result of poor lubrication, the high temperature can cause the plastic casing of the crank sensor to melt or crack. If this takes place, the car will not start because the sensor cannot relay crankshaft information back to the computer.
- Faulty Wiring Harness: A faulty wiring harness can result from improper voltage, ground or loose circuit problems, loose wiring, oil and debris. This can cause the repeated failure of the sensor. As a result, the vehicle may crank but not stay on.
- Damaged Timing Belt: A damaged timing belt, either as a result of collision or wear and tear, can get wrapped around the crankshaft and damage numerous small parts and sensors. If the crank sensor was struck by the timing belt when it snapped, it can result in damage to the wiring harness and the sensor.
Symptoms of A Faulty Crankshaft Position Sensor
The proper functionality of your camshaft is crucial for the effective running of your vehicle. Driving without it can also cause irreparable damage. Hence, looking out for signs indicative of a faulty crankshaft position sensor will help you avoid costly repairs.
- Stalling: One of the most common signs of a faulty crankshaft position sensor is intermittent stalling of the vehicle. The electronic control unit will not receive any reliable signal interfering with the timing system. Since it is the most important of all engine management sensors, the car’s engine cannot run without it.
- Engine Misfiring or vibration: Another symptom is the misfiring or vibration of the engine. A brief stutter in the engine may be a sign of misfiring cylinders from a bad crankshaft position sensor. If the sensor is bad, it cannot provide the right information about piston positioning in the engine.
- Uneven Acceleration: Inaccurate input from the crankshaft position sensor, prevents the engine control unit from making the necessary adjustments to spark timing and fuel injection as the engine speed This results in dragging acceleration which makes it difficult to maintain speed.
- Inadequate Fuel Injection: The result of lack of accurate timing information from the crankshaft position sensor is that the fuel injectors will not pump gas into the engine efficiently. This will make the engine use more gas than it needs and reduce overall fuel economy.
Import Car Center for Quality Service and Repairs
The purchase of a European vehicle is a long-term investment and should be protected and maintained with the best quality service. When it comes to taking care of cars, Import Car Center understands the importance of excellence.
We understand that each European vehicle has its unique service needs and maintenance programs to perform at their best. Our certified mechanics have decades of experience and employ the latest factory-grade tools and equipment available. This allows our technicians to handle everything your car needs in-house.
We are located in Grapevine, TX, and we have stayed committed to helping drivers throughout Grapevine and the surrounding areas of Colleyville, Keller, Southlake, and Westlake with quality repairs and maintenance. Please call or visit our shop today to schedule your car’s next service appointment!