The cooling system in an internal combustion engine vehicle keeps the engine running at its ideal temperature and guards against overheating. The temperature of the liquid coolant is measured by an ECT, or engine coolant temperature sensor.
A popular engine cooling temperature sensor is an NTC (Negative Temperature Coefficient) thermistor, meaning that as the temperature rises, it becomes less resistive electrically.
The ECT sensor’s tip extends into a passageway of the cooling system and is submerged in coolant. Many automobiles feature multiple coolant temperature sensors. The primary ECT sensor (ECT sensor 1) is typically mounted on the thermostat housing, cylinder head, or block, which is close to the thermostat.
Well, in today’s car guide, we’ll be educating you on a car coolant temperature sensor, its symptoms, location, cost replacement and how it works.
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Let’s Begin!
What is a coolant temperature sensor?
A coolant temperature sensor, also known as an engine coolant temperature sensor (ECT sensor), is a device used in vehicles to monitor the temperature of the engine coolant.
In other words, the engine coolant temperature is measured by a resistor circuit through the coolant temperature sensor.
This reading is then transmitted to the Engine Control Module (ECM) or Engine Control Unit (ECU), which serves as the vehicle’s “brain.
It is usually seen on the cylinder head, engine block, or intake manifold. The engine control unit (ECU) or engine management system receives the information from the coolant temperature sensor, which detects the coolant’s temperature.
Important choices about fuel injection, ignition timing, and other engine functions are made by the ECU using this information.
Function
In order to keep the engine working at its ideal temperature, the coolant temperature sensor is essential. It aids in preventing the engine from overheating or operating too coldly, both of which can have an impact on output, fuel economy, and pollutants.
The sensor helps in regulating the air-fuel mixture and chooses the right moment for ignition by keeping track of the coolant temperature.
The engine performance may be affected in a number of ways if the coolant temperature sensor is defective or malfunctioning. For instance, incorrect temperature measurements may result in faulty fuel delivery, which could reduce fuel efficiency or make it harder to start the engine.
A malfunctioning sensor may also cause the engine to overheat or turn on the check engine light.
How does it work?
The coolant temperature sensor works similarly to an engine thermometer in your car. It measures the temperature of the engine coolant. It makes use of a unique component known as a thermistor, whose electrical resistance varies depending on the temperature. The engine control unit (ECU), which functions as the car’s “brain,” is connected to the sensor.
The coolant temperature is represented by an electrical signal that the thermistor gives to the ECU. This temperature data is used by the ECU to make critical choices regarding the engine’s operation.
For instance, to maintain the engine operating properly, it modifies the fuel mixture and ignition timing dependent on the coolant temperature.
Problems may arise if the coolant temperature sensor is not functioning properly. It’s possible that the ECU is unaware of the actual temperature, which might cause problems like poor fuel economy or engine overheating.
In general, the coolant temperature sensor aids the computer of the vehicle in maintaining the engine at the proper temperature for maximum effectiveness and efficiency.
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Where is the coolant temperature sensor located?
Depending on the make and model of the car, the location of the coolant temperature sensor may change. However, in most vehicles, the coolant temperature sensor is typically located near the engine’s thermostat housing or on the engine block itself.
Usually, it’s located next to the radiator hose or in a coolant passage. Consult your vehicle’s owner’s manual or repair manual for a specific answer. These resources often provide detailed information and diagrams to help locate the coolant temperature sensor accurately.
What are the symptoms of a defective coolant temperature sensor?
When your coolant temperature sensor is malfunctioning, you’ll typically notice the following symptoms:
Engine Overheats:
A broken coolant temperature sensor may send an inaccurate “cold” signal to the ECU, tricking it into believing the engine isn’t hot enough. The engine will then continue to heat up and eventually overheat as a result of the ECU making adjustments to the fuel injection, ignition timing, and variable valve timing.
Trouble Starting Your Car:
The ECU determines the necessary fuel-air mixture ratio when you cold-start your automobile by taking into account the coolant and outside temperatures. Faulty coolant temperature sensors can sometimes cause lean fuel-air mixtures, which can make cold starts challenging.
Exhaust Removes Black Smoke:
The coolant temperature sensor in your automobile works with the ECU to select the right fuel-to-air ratio for combustion. A malfunctioning sensor might cause a rich fuel-air mixture, which would result in black smoke coming out of the exhaust pipe and poor fuel efficiency.
Check Engine Light is on:
The ECU may turn on the check engine light on your car’s dashboard as a result of a defective sensor. Additionally, it will record an error code that an OBD-II scan tool may interpret.
Car Idles Roughly:
The Engine Control Unit may deliver varying amounts of fuel into the engine as a result of a broken ECT sensor, causing the engine to idle unevenly.
Temperature Gauge Fluctuates:
The coolant temperature sensor provides data to the engine temperature gauge on your car’s dashboard. If a sensor breaks, the engine temperature gauge may fluctuate erratically while you drive.
Transmission Shifting Faults:
The coolant temperature sensor reading is used by the Transmission Control Module (TCM) to prevent the automobile from going into overdrive while the engine is cold. Reduced engine performance and transmission issues can result from the sensor’s inaccurate data.
Problems With the Radiator Fan:
Due to a malfunctioning coolant sensor, the Engine Control Unit of your car may activate the radiator fan even when the engine isn’t hot enough. Conversely, the sensor might fail to activate the fan when needed, causing the engine to overheat and sustain damage.
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How much does a coolant temperature sensor cost?
Depending on the car model and labour expenses, the cost to repair a coolant temperature sensor ranges from $50 to $250. A coolant temperature sensor can be bought for $30 to $100 in addition to the labor cost.
A good coolant temperature sensor typically costs around $40. There are less expensive models available, but to avoid headaches, I strongly advise purchasing a high-quality model like Bosch.
The replacement is frequently relatively simple, except that you might need to drain and refill the entire engine’s coolant. Removing the coolant also requires removing all the air from the coolant system, which is difficult.
However, if you replace the sensor quickly, you may avoid having to tap out the coolant, though doing so requires some ability.
FAQs
What happens when the coolant temperature sensor goes bad?
When a coolant temperature sensor goes bad, it can lead to symptoms such as inaccurate temperature readings, engine overheating, difficulty starting the engine, poor fuel efficiency, and problems with the cooling fan operation.
How do you know a coolant temp sensor is bad?
Signs of a bad coolant temperature sensor include inaccurate temperature readings, fluctuating temperature readings, engine overheating, poor fuel efficiency, difficulty starting the engine, and abnormal cooling fan operation.
What does a coolant temperature sensor do?
A coolant temperature sensor monitors the temperature of the engine coolant. It sends this information to the engine control unit (ECU) to make adjustments to fuel injection, ignition timing, and cooling system operation for optimal engine performance and to prevent overheating.
Do coolant temperature sensors prevent the engine from overheating?
Coolant temperature sensors contribute to preventing engine overheating. They provide temperature information to the ECU, which controls the cooling system to maintain the engine within the desired temperature range.
What causes a temperature sensor to fail?
Temperature sensor failure can be caused by electrical or wiring issues, exposure to extreme temperatures, contamination or build-up, corrosion or damage to the sensor, aging, or manufacturer defects.
Can a car run without a coolant sensor?
A car can technically run without a coolant sensor, but it is not advisable. Operating without a functioning coolant sensor can lead to engine damage, reduced fuel efficiency, and increased emissions.
Does the coolant temp sensor control the fan?
The coolant temperature sensor provides temperature information to the ECU, which controls the operation of the cooling fan based on the readings received.
Are there 2 coolant temperature sensors?
Some vehicles may have multiple coolant temperature sensors. The number of sensors can vary depending on the vehicle’s make, model, and engine configuration.
What can affect a temperature sensor?
Factors that can affect a temperature sensor include contamination, wiring or electrical issues, corrosion, vibration or physical damage, exposure to extreme temperatures, and aging or wear.
Is a temperature sensor and coolant sensor the same?
Yes, a temperature sensor and a coolant sensor are often used interchangeably. The coolant temperature sensor measures the temperature of the engine coolant to provide temperature data for the engine control system.