Understanding Camshaft Position Sensor

A camshaft position sensor is found in every modern automobile. This sensor is an essential component of any car since it ensures that the engine is operating correctly. When looking under the hood of your car, you can have problems finding the sensor. Typically, each car manufacturer will have its unique location for putting the sensor near the engine. It can be found behind the cylinder head, in the vehicle’s lifter valley, or adjacent to the engine block.

A camshaft position sensor’s job is to figure out where the camshaft is with the crankshaft. The powertrain control module (PCM) receives this information and uses it to operate the fuel injectors and/or ignition system.

In this article, you’ll learn the definition, functions diagram, working, and symptoms of a bad camshaft position sensor.

camshaft-position-sensor

Contents

What is a camshaft position sensor?

The camshaft position sensor keeps track of the camshaft’s rotation, focusing on when valves open and close. The majority of camshaft sensors are located right above the camshaft’s notched ring. The majority of these camshaft sensors will employ a magnet to generate or alter an AC electrical signal, which will be utilized in conjunction with a crankshaft position sensor to determine when a position approaches the top dead center (TDC) on the compression stroke. This data will aid in the fine-tuning of spark timing and injector pulse. it is also called a cylinder identification sensor or phase detector.

The ECU in a sequential fuel injection system must decide which cylinder to ignite next. The cylinder identification sensor provides this information. Whenever the first cylinder is at the top dead center during engine rotation, the sensor transmits a signal to the onboard controller (TDC).

Functions of Camshaft position (CAM) sensor

The followings are the common functions of a camshaft position sensor:

  • To determine which cylinder is on its power stroke, a camshaft position (CMP) sensor is used by the car’s computer to monitor the rotating position of the camshaft relative to the crankshaft position. This information will be used to alter the spark timing and fuel injector operation.
  • The CAM sensor, also known as the camshaft position sensor, is responsible for informing the ECM of the camshaft position. The crank and cam sensors are in time with one another. In a sequential system, the CAM sensor is typically employed to determine which injector to fire and for the COP or coil-on-plug ignition system coil firing event.

The camshaft position sensor collects and communicates data on the vehicle’s camshaft speed to the engine control module (ECM). This information is used by the ECM to determine the ignition timing as well as the timing of the fuel injection required by the engine. The engine would not be able to work effectively without this information.

Diagram of CAM position sensor:

camshaft-position-sensor-diagram

Working Principle

The working of a camshaft position sensor is less complex and can be easily understood. just as earlier stated, The ECU in a sequential fuel injection system must decide which cylinder to ignite next. The cylinder identification sensor provides this information. Whenever the first cylinder is at the top dead center during engine rotation, the sensor transmits a signal to the onboard controller (TDC).

Working of a camshaft position sensor

As a result, the duration of the pulse injection may be calculated. The onboard controller in simultaneous fuel injection systems does not identify the cylinders or the firing sequence because it is not required for the system to function. The exact cylinder is determined when a crankshaft or distributor advance ignition signal comes by detecting the mechanical locations of the crankshaft, camshaft, valves, or distributor shaft.

Watch the video below to learn more about the working of a camshaft position sensor:

Common Symptoms of a bad camshaft position Sensor

The followings are the symptoms you experience when a camshaft position sensor is faulty:

Check Engine Light is on:

When your camshaft position sensor fails or starts to malfunction, the first thing you should notice is that your dashboard’s “Check Engine” light illuminates. Obviously, the “Check Engine” light could signal a lot of issues, including a malfunctioning camshaft position sensor.

Ignition Problem:

If the camshaft position sensor fails while you’re driving, the engine will occasionally lose power, causing your car to shake or surge forward at random. These are both caused by the PCM receiving inaccurate information from the camshaft position sensor, resulting in an incorrect quantity of fuel being pumped into the cylinders.

Engine Stalling:

Even worse than not being able to start your automobile is having your engine shut down or stall while driving because the fuel injectors aren’t being told to feed fuel into the cylinders.

Poor Acceleration:

When your camshaft sensor begins to fail, your vehicle will jerk and be unable to accelerate quickly. In certain circumstances, you’d be lucky if you got past 30 miles per hour. Incorrect fuel supply by the injectors is again to blame for the weak acceleration.

Problem Shifting:

Certain models of cars with a faulty camshaft position sensor will develop a locked transmission, which will remain in a single gear. The only way out of that gear is to turn off your engine, wait a few moments, and then restart.

Bad Fuel Mileage:

This is the opposite of not giving the engine adequate gasoline. Because of an inaccurate reading from a malfunctioning camshaft position sensor in this situation, more fuel is pumped into the engine than is required, lowering your fuel economy.

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Conclusion

A camshaft position sensor keeps track of the camshaft’s rotation, focusing on when valves open and close. The majority of camshaft sensors are located right above the camshaft’s notched ring. The majority of these camshaft sensors will employ a magnet to generate or alter an AC electrical signal, which will be utilized in conjunction with a crankshaft position sensor to determine when a position approaches the top dead center (TDC) on the compression stroke. That is all for this article, where the definition, functions, diagram, working principle, and symptoms of a bad camshaft position sensor are been discussed.

I hope you learn a lot from the reading, if so, kindly share with other students. Thanks for reading, See you around!

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