Through technology, cars and their on-road as well as off-road performance have been upgraded to a level of utmost magnificence. That is why cars these days are outfitted with computer management systems in different components for varying functions. As a result they provide driving excellence. One such technological advancement in this field that has furthered the capacity of cars is the crankshaft position sensor. With the role of acting as a monitor, a crankshaft position sensor detects the exact degree or angle that a crank is at during rotation. The crankshaft position sensor is fitted onto your car in order to maximize operational proficiency. Particularly, as the turning of a crankshaft goes, the crankshaft position sensor will alert the car's Powertrain Control Module which is considered as the brain center of the car engine's control system. It then in turn will let the engine provide the needed spark as well as fuel which is needed for optimum car engine performance. To ensure that you get only the finest quality crankshaft position sensor replacements for whatever make or model your car may be, do browse through CarParts' wide catalogue. At CarParts, you're sure to find that our prices are easy on the budget as well.
Crankshaft Position Sensor Buyer’s Guide
- The crankshaft position sensor is one of the two most important sensors found inside your car along with the camshaft position sensor.
- The crankshaft position position sensor is commonly mounted close to the crank pulley on most cars.
- The different types of crankshaft position sensors are magnetic pick-up coil, hall-effect, and optical sensors.
- The signal from the crankshaft position sensor is used by the powertrain control module to time the spark in the right cylinder.
- Excessive engine heat, a damaged reluctor ring, and bad wiring harnesses can cause the crankshaft position sensor to fail.
- OE replacement crankshaft position sensors on CarParts.com are priced anywhere between $2 and $440.
Part of every internal combustion engine are sensors that ensure that all components inside the engine are working efficiently. This is very important if you want to preserve your car’s engine performance, fuel efficiency, and ride quality. Two crucial sensors under the hood of your car, known as the crankshaft position sensor and camshaft position sensor, keep most of the components inside your engine in sync.
Camshaft position sensors are usually used on vehicles with engines that feature distributorless ignition systems as well as sequential fuel injection. It transmits information about the camshaft’s position to the engine’s control module. The module would then use this to correct the pulsing sequence of the fuel injectors and match it to the engine’s firing order. But what about the crankshaft position sensor?
What is a crankshaft position sensor?
The crankshaft position sensor is one of the two most important sensors found inside your car along with the camshaft position sensor. Both sensors are used simultaneously to monitor the proper timing of pistons and valves in the engine, especially in powertrains with variable valve timing. A crankshaft position sensor is a small piece of equipment with varying shapes and designs, which ensures smooth engine operation and efficiency.
Where is the crankshaft position sensor?
The crankshaft position position sensor is commonly found mounted close to the crank pulley on most cars. However, there are other mounting positions where it is sometimes installed, such as near the transmission bell housing, in the engine cylinder block, or on the crankshaft itself. It is oriented in a position that directly faces the teeth of the reluctor ring, which is attached to the crankshaft. This reluctor ring normally has a tooth missing to serve as a reference point for the powertrain control module.
Types of crankshaft position sensors
Crankshaft position sensors not only differ in size and shapes as they also feature varying mechanisms. Here are the three most common types of crankshaft position sensors.
Magnetic pick-up coils sensors
This type of crankshaft position sensor reads the slots in a reluctor ring on the flywheel. It relies on the teeth of the reluctor ring as it comes in proximity of the sensor for it to create pulse signals based on the changes in magnetic field.
The hall-effect crank position sensor reads a notched metal interrupter ring behind the harmonic balancer. This type of crankshaft position sensor sends an on-off signal to the powertrain control module so it can monitor the engine rpm and positioning of the crank.
Unlike the two aforementioned sensors that uses the metal teeth of the reluctor ring, optical crankshaft position sensors utilize light-emitting diodes (LED) and photodiodes to read the markings on the shaft. These sensors are acknowledged for their accuracy and their reliability at high-speeds.
What does a crankshaft position sensor do?
The crankshaft position sensor monitors the rotational speed of the crankshaft. Aside from this, it also measures the precise position of the engine crankshaft that makes it possible for your engine to run smoothly. All of this information is relayed to the vehicle’s onboard computer to control the fuel injection, ignition system timing, and a few other engine parameters.
The crankshaft position sensor produces a pulsed signal in correspondence with the teeth of the reluctor ring as the crankshaft rotates. The signal is then used by the powertrain control module to time the spark in the right cylinder. Without these signals, the fuel injectors won’t work and spark won’t be initiated properly.
What causes a crankshaft position sensor to go bad?
The crankshaft position sensor is essential in synchronizing the crankshaft’s rotational speed and positioning by sending precise information to the onboard system. It is important that this device is working properly to ensure uncompromised engine performance. The crankshaft position sensor can fail due to the following:
Excessive engine heat
The crankshaft position sensor’s housing is made of plastic material. If the engine gets too hot, which could be due to an existing cooling system problem, the plastic casing could melt and damage the crankshaft sensor.
Bad wiring harnesses
Beware of loose or improper connection of wiring harnesses as they can cause circuit problems, which could lead to voltage disruption. The intermittent voltage supply can fry the crankshaft position sensor and put it out of commission sooner than expected.
Damaged reluctor ring
Since the crankshaft position sensor relies on the metal teeth of the reluctor ring to come up with an accurate reading, the reluctor ring plays an important role in ensuring precise data. A damage in the reluctor ring, such as a missing tooth, may disrupt the pattern and render incorrect information on the crankshaft’s rotational speed. This could damage the crankshaft position sensor in the long run.
Symptoms of a bad crankshaft position sensor
To avoid further damage in your ignition system or the engine itself, pay close attention to these bad crankshaft position sensor symptoms.
Difficulty starting the engine
The engine may not start if the crankshaft position sensor isn’t working properly. Monitoring the crankshaft’s position and speed is vital when starting the engine, as the data is used by the powertrain control module to control the spark and fuel injection. As a result, you could have problems starting your vehicle from time to time.
Another symptom of a malfunctioning crankshaft position sensor is associated with engine stalling. Although this is usually a sign of wiring issues, intermittent stalling can also be due to a failing crankshaft position sensor mainly because it can interfere and cut the signal that’s being sent to your vehicle’s computer while the engine is running. This causes your vehicle to stall.
Illuminated Check Engine Light warning
It’s no secret that the Check Engine Light on the instrument cluster means there are issues related to your engine that you need to check. It can also be triggered if the computer detects any anomalies relating to the crankshaft position sensor’s signal transmission.
Engine misfire and rough vibrations
You may also start to feel jerkiness caused by the engine when idling. This is due to misfiring in the cylinder, which may be a result of a bad crankshaft position sensor that causes incorrect spark plug timing.
Poor fuel economy
If your crankshaft position timing isn’t working properly, the fuel injector may pump fuel into the cylinder insufficiently. This may also lead to engine misfire and your vehicle’s fuel economy will surely suffer.
How much is a crankshaft position sensor replacement?
Crankshaft position sensor replacements should cost you around $100 to $120. Good thing is that CarParts.com offers special deals for crankshaft sensors if you’re on a tight budget. OE replacement crankshaft position sensors on CarParts.com are priced as low as $2. Premium quality crankshaft position sensor upgrades, on the other hand, are also available and could cost you around $440. Items are sold individually, in sets of two, or as part of a kit. Simplify your browsing by indicating your vehicle’s year, make, and model on the filter tab under the search menu.
Getting a New Crankshaft Position Sensor
What does the crankshaft position sensor do?
This device, also known as an engine speed sensor, monitors the position and rotational speed of your crankshaft. By doing so, it provides your engine control unit the information it needs to properly time certain operations likeinjecting fuel and triggering spark plugs.
When should a crankshaft position sensor be replaced?
A faulty crankshaft position sensor means your engine will not be able to run efficiently, and you will experience problems like cylinder misfires, difficulty accelerating, and, in worst cases, being unable to start your vehicle or the engine abruptly failing. However, before getting a replacement, we recommend going to any auto parts chain store and having them read the codes in your vehicle's computer with a scanner. This will determine if the problem is really with your sensor and not from any other component.
Which crankshaft position sensor should be used?
You will need to refer to your vehicle's owner manual in order to find out what specific crankshaft position sensor is compatible with your vehicle. However, there are generally two types of crank sensors: magnetic field (also known as variable reluctance) and Hall Effect.
The magnetic type works by having a strong magnet mounted near the crankshaft, in which several pins are placed at an equal distance apart. The magnet creates a constant magnetic field, which fluctuates when the crankshaft spins and the pins rotate. The magnetic fluctuations produce alternating current signals, the frequency of which gives your engine control unit the information it needs to control timing.
The Hall Effect sensor uses notches on the crank to disrupt its magnetic fieled. This causes the sensor to switch onand off, this giving a digital signal to your engine control unit.
Both types are highly successful sensor systems. Generally however, Hall Effect sensors are more complex and have smoother operational function while magnetic field sensors are capable of withstanding higher temperatures.
What other factors are considered in choosing a crankshaft position sensor?
- Installation - If your sensor is located on the side of the engine, chances are that you will need to install a new rubber O-ring. See if you can order a replacement package that also includes new O-rings as well as other components you may need for installation.
- Heat Resistance - The plastic casing of crankshaft sensors have been known to melt or crack under extreme engine temperatures. A good range of temperature tolerance would be from -40 degrees Fahrenheit to 300 degrees Fahrenheit.
Replacing Your Crankshaft Position Sensor
Also known as an engine speed sensor, your crankshaft position sensor monitors the position and rotational speed of your crankshaft. This enables your engine management system to properly time certain operations like injecting fuel and triggering spark plugs. Without this component, your engine will not run efficiently, and you will experience some of these problems:
- Difficulty accelerating
- Multiple cylinder misfires
- Vehicle bucks and surges
- Inability to start or idle
You will also notice that the "Check engine" light is on. To be sure the problem is with your crankshaft position sensor, we recommend going to any auto parts chain store and having them read the codes in your vehicle's computer with a scanner. Some stores may even do this for free.
A malfunctioning crankshaft position sensor should be replaced immediately.
Here's what you'll need:
And here are the steps:
- Screwdriver or socket wrench (depending on the retaining bolt)
- Rubber O-ring (optional)
- Paper spacer (optional)
- Replacement crankshaft position sensor
- Vehicle owner manual
- Safety gloves
- Disconnect your battery to prevent any electrical malfunction.
- Find your crankshaft position sensor. Common places are the front, rear, or side of the engine, behind the crankshaft pulley, or under the timing cover. Your vehicle's owner manual should tell you exactly where it is.
- Disconnect the three wires leading to your crankshaft sensor. Keep track of the wires and how they were connected to the sensor. You will need to reconnect them in the same way with your replacement sensor.
- Remove any retaining bolts then lift crankshaft position sensor off the engine.
- Install your replacement sensor and connect the three wires. It should lock into position without the need for any adjustments. You may need to install the rubber O-ring if the sensor is on the side of the engine (do not re-use the old O-ring). If any adjustment is necessary, use the paper spacer on the end of the sensor.
- Tighten any retaining bolts firmly. Take care not to over tighten them for this may damage the sensor.
- Reconnect your battery.
Things to Consider When Looking for a Crank Position Sensor
With the right information from the crank position sensor, your vehicle engine is able to maintain ignition timing. This is why if this sensor fails, you’re likely to experience a variety of engine problems. Fortunately, it’s easy to replace this component as long as you have the right tools, basic repair skills, and of course, a high-quality replacement sensor. To make sure that you’re making the right choice when shopping for a replacement, here are features you should look into:Heat resistance
One of the most common culprits behind a malfunctioning sensor is damage due to extreme heat. Keep in mind that this component is usually located on the side of the engine block or in the timing cover and will be subjected to extreme heat on a regular basis. As such, a sensor made from high-grade materials that won’t easily wear out due to extreme temperatures is a good investment.Circuitry
A good sensor should be backed by a high-tech circuitry to prevent power spikes and stray magnetic fields, especially since many American vehicles are equipped with sensors that rely on magnetic pulses. Now of course you won’t be able to really see the circuitry inside while shopping. So the next best thing is to check out top brands and read a bit about how they make their sensors. By arming yourself with the right information, you should be able to choose a sensor with a reliable circuitry.Manufacturing condition
When shopping for a replacement sensor, you basically have two options in terms of manufacturing condition: remanufactured or brand new. Keep in mind that a remanufactured part is just as good as a brand-new one. As a matter of fact, many reliable manufacturers rebuild certain auto parts because it helps conserve energy, raw materials, and landfill space. When opting for a rebuilt component, make sure the product is designed and tested to meet or exceed industry standards and is made to match your vehicle’s specs.
Aside from these factors, don’t forget to check a product’s brand, warranty, and price. Since many reliable manufacturers offer a lot of options at affordable prices, you won’t have a hard time in finding one that will match your car’s specs and fit your budget.
Car Care 101: Replacing a Crank Position Sensor
A busted crank position sensor can be such a headache. Aside from ignition backfires, it can also lead to engine stalling and start-up problems. Fortunately, replacing this sensor is easy. Once you’ve found a direct-fit replacement, here’s what you have to do:Difficulty level: ModerateTools needed:
- Paper spacer (optional)
- O-ring (optional)
- Socket wrench or screwdriver
Step 1: Prep your vehicle. Before you start tinkering under the hood, make sure that the battery’s negative cable is disconnected. This is to prevent short circuits that can easily damage your vehicle’s control module.
Step 2: Locate your car’s crank position sensor. It’s usually located at the side, rear, or on the front part of the engine near the main pulley. However, since its exact location depends on your car’s year, make, and model, better check the vehicle manual to help you find this component.
Step 3: Disconnect the sensor wires. Once you’ve located the sensor, you’ll see that it’s connected to your car’s electrical system through a set of wires. Remove the wire harness by pulling it out, taking note of the order of the wire connections. There are usually three wires: one for the current feed, one for the ground, and another one for the output.
Step 4: Remove the old crank position sensor. After removing the wire harness in order to disconnect the three wires, pry out the bolt that holds the sensor in place with a socket wrench. Then pull out the old sensor. Depending on your car make and model, you might also need to pull out an o-ring or rubber seal that secures the old sensor in place.
Step 5: Attach the new sensor. Place the new sensor in position, following the original placement of the old part. If your car uses a sensor gasket, install a new one—never reuse the old gasket. Place the new o-ring around the sensor and push it in place. Once the sensor and gasket are locked in together, reconnect the wire harness; make sure you follow the original order of the wires. If you notice that the sensor doesn’t lock into place, you can adjust it with a paper spacer. After adjusting and checking that every part removed was reinstalled, reconnect the battery and take your car for a test drive.