Mercedes Crankshaft Sensor - VNE 0031539628

Product Information

The engine crankshaft position sensor monitors the position and rotational speed of the crankshaft, providing information to the engine control unit (ECU). The sensor ensures proper timing for fuel injection, ignition, and other key engine functions. Without accurate crankshaft data, the ECU can't adequately time the spark or fuel, causing poor performance or even preventing the engine from running. Crankshaft position sensors come in different designs, with magnetic or Hall-effect sensors being the most common. The magnetic sensor consists of a coil and magnet that generates a signal as the engine rotates, while the Hall-effect sensor uses a semiconductor to detect changes in the magnetic field.

The crankshaft position sensor is usually located near the crankshaft pulley/harmonic balancer, or flywheel/transmission depending on the engine’s design. It works by detecting notches or teeth on a component called a reluctor or tone wheel, creating a signal that the ECU can interpret. When this sensor fails, common symptoms include engine stalling, rough idling, misfires, or the engine not starting at all. One of the most frequent failure modes is internal short-circuiting due to heat and vibration over time. Contaminants like oil, dirt, or metal shavings can also interfere with its ability to detect the crankshaft's position.

• No Start Condition: The CPS gives the information to the ECU that the engine is showing positive RPM and is ready to start. If the computer does not get a signal from the sensor, or the sensor is outputting values that it is not anticipating, the engine won’t start.
• Stalling when warm: Once the engine warms up, a failing crankshaft position sensor can often cause stalling when coming to a stop because the engine doesn’t have the right information to maintain a stable idle.
• Dead or erratic tachometer: Some older vehicles may run the tachometer off of the output from the crankshaft sensor. If the tach is behaving strangely, especially in conjunction with other running problems, the CPS could be at fault.
• P0335: If the integrity of the internal wiring has failed, you may get a P0335, however it is not a guarantee that a vehicle with a failing CPS will have a check engine light.
• Poor performance at certain RPMs: A failing crankshaft position sensor can cause issues with engine performance, especially if at a certain point in the rpm range the sensor can’t send an in-range signal to the ECU with may cause timing to drift. Failing crank position sensors more commonly cause running issues at higher RPMs and idle.
• Misfires across multiple cylinders: If the engine is struggling to time fuel and spark, you may encounter misfires across all cylinders at once. This is in contrast to the failure of a coil or fuel injector, which may only effect one cylinder at a time.

About VNE

VNE GmbH was founded in 2001 by Volker Natorp in Hamburg, Germany. Volker has a long, storied history in the automotive field. He began his career in the 1970s working for Wulf Gaertner and in the 1990s eventually branched out on his own to start his own sales repping agency. During that time, he represented TMD Friction (Pagid/Textar) and managed all of the North American sales for them and eventually added Schaeffler Automotive to his roster.

In 2007, VNE GmbH relocated to Ganderkesee, Germany and was renamed VNE Automotive GmbH & Co. With continuous growth, the decision was made to solely focus on developing VNE Automotive and, in 2014, the focus became reality with the commissioning of a new warehouse and office space. Today, VNE Automotive prides itself on never having followed the aftermarket trend. VNE Automotive operates in a highly specialized, niche product sector, by only offering OEM automotive spare parts to more than 50 countries worldwide. This is evident from the unique, and sometimes hard to find, product groups spanning engine management, body electrical, and brake systems.