The Camshaft sensor determines which cylinder is firing to establish injector synchronization and coil firing sequence in DIS systems. Crankshaft sensors set ignition timing, supply the RPM signal, and determine engine speed.
These two types of sensor help the electrical control unit (ECU) calculate the position of two key parts of the engine: the camshaft and the crankshaft. The crankshaft position sensor is attached to the engine block facing the timing rotor on the crankshaft.
The camshaft controls the opening and closing of valves through the combustion process, and the crankshaft takes the energy from that process and connects it to the rest of the vehicle.
Camshaft position sensor is also called cylinder identification sensor or phase detector. In consecutive fuel injection systems, ECU must determine which cylinder to fire next. This information is provided from the cylinder identification sensor.
The crankshaft and the camshaft play a vital role in this process. These two components are what help convert the movement of the pistons into the power it takes to turn the wheels of your vehicle. The crank and the cam are shafts located inside your vehicle's engine.
A camshaft sensor determines the exact position of your engine's camshaft, helping your car keep your engine's combustion running smoothly. Many modern engines have one camshaft sensor for each camshaft. This can mean up to four, although some cars will only have two.
Timing gear
The camshaft is driven around by a toothed gear, which receives drive through the timing belt or chain, from the crankshaft. The four-stroke cycle requires two rotations of the crankshaft for a complete cycle, and so the camshaft is driven at half the speed of the crankshaft.
If you ignore the symptoms listed here and your camshaft position sensor fails, your vehicle will not start. As a camshaft position sensor weakens, so does the data it transmits to the ECM. Eventually the data signal becomes so weak the ECM switches off fuel and spark delivery, and your engine will not start.
Because one turn of the camshaft completes the valve operation for an entire cycle of the engine and the four-stroke-cycle engine makes two crankshaft revolutions to complete one cycle, the camshaft turns half as fast as the crankshaft.
The most important sensors of any engine, the crankshaft and camshaft position sensors are integral to the functionality of the distributor and ignition timing. The crankshaft position sensor monitors as a multifunctional sensor used to set ignition timing, detect engine RPM and relative engine speed.
Camshaft and crankshaft sensors monitor the position of the engine's crankshaft and camshaft by generating an electrical signal based on the position of the trigger wheel (variable reluctance sensor) or metal rotor (Hall effect sensor).
The crankshaft and both camshaft position sensors should be replaced at the same time.
The crankshaft position sensor is the most important of all engine management sensors, and the engine will absolutely not run without it.
Common signs of a faulty crankshaft position sensor include issues starting the vehicle, intermittent stalling, and the Check Engine Light coming on.
As the camshaft position sensor weakens, the signal it transmits to the vehicle's ECM also weakens. Eventually, the signal will weaken so much the signal will switch off, and so will the engine. This can happen while the vehicle is parked, or while you are driving. The latter can be a dangerous situation.
There are a number of reasons your camshaft sensor might break down: grime and oil in the engine, water damage, bad wiring, and overheating can all cause a camshaft sensor to go bad. The biggest thing to do to avoid this is to take care of your car.
The main causes may be a damaged timing belt, bad wiring, overheating, crank walks, etc. Some of these also include wear-and-tear, water damage, and oil embedded in the engine, these can also damage the engine's camshaft since these things will build up over time.
The camshaft position sensor on a car is built to last as long as the car does, but in most cases it will have to be replaced well before that. Just like any other sensor or switch on a car, the camshaft position sensor will take a lot of abuse due to the heat that the engine produces.
Code P0340 indicates there is a problem with the electrical wiring of the circuit attached to the camshaft position sensor. This issue can result in the display of a multitude of other codes that relate directly to your vehicle's camshaft. In addition, your powertrain control module (PCM) could also be damaged.
Changing a cam sensor isn't an overly complicated job, but it requires some basic tools and a code reader to get the job done right.
Cost to Replace a Camshaft Sensor
A camshaft position sensor replacement is not an expensive job, if diagnosed properly. Some vehicles may have a lower cost, but expect a cost of between $200 and $400 for mainstream cars to replace the camshaft position sensor.
The PCM uses the signal from the crankshaft position sensor to determine when and in which cylinder to fire the spark. The signal from the crankshaft position is also utilized to check for misfires in the cylinders. There will be no spark and the fuel injectors will not operate if the sensor signal is missing.