How much does it cost to replace an engine coolant temperature sensor?

The cost to replace an engine coolant temperature sensor can vary depending on the make and model of your vehicle, as well as the labor costs associated with the repair. On average, you can expect to pay between $100 and $300 to have an engine coolant temperature sensor replaced by a professional mechanic.

What is an Engine Coolant Temperature Sensor?

The engine coolant temperature sensor, also known as the ECT sensor, is a crucial component in your vehicle's cooling system. It is responsible for monitoring the temperature of the engine coolant and relaying that information to the vehicle's computer, known as the Engine Control Unit (ECU). The ECU then uses this data to adjust the engine's fuel and ignition timing, ensuring optimal performance and fuel efficiency.

Why Would You Need to Replace the Sensor?

There are a few common reasons why you might need to replace the engine coolant temperature sensor:

• Sensor Failure: Over time, the sensor can wear out or become damaged, leading to inaccurate temperature readings or a complete failure of the sensor.


• Engine Overheating: If the sensor is not accurately reporting the coolant temperature, it can cause the engine to overheat, which can lead to further damage if not addressed.


• Decreased Fuel Efficiency: An faulty coolant temperature sensor can cause the engine to run inefficiently, leading to decreased fuel economy.


• Illuminated Check Engine Light: A problem with the coolant temperature sensor will often trigger a check engine light, alerting you to the issue.

If you notice any of these symptoms, it's important to have the sensor inspected and replaced if necessary to prevent further damage to your vehicle.

Factors Affecting the Replacement Cost

The total cost to replace an engine coolant temperature sensor can vary based on a few key factors:

• Part Cost: The cost of the replacement sensor itself can range from $20 to $100 or more, depending on the make and model of your vehicle.


• Labor Costs: The labor required to access and replace the sensor can add an additional $50 to $200 or more, depending on the complexity of the job and the hourly labor rate of the mechanic.


• Location of the Sensor: Some vehicles have the coolant temperature sensor located in a more accessible area, while others may require more extensive disassembly to reach it, increasing the labor time and cost.


• Diagnostic Fees: Some mechanics may charge a diagnostic fee to identify the problem and determine the appropriate replacement part.

It's always a good idea to get quotes from multiple mechanics or repair shops to ensure you're getting a fair price for the coolant temperature sensor replacement.

Is it expensive to fix a coolant temperature sensor?

The estimated cost to replace a coolant temperature sensor is typically between $70 and $330, depending on the vehicle's make and model. The cost is comprised of the part itself, which can range from $20 to $80, and labor, which can range from $50 to $250. Some difficult-to-access sensors or certain vehicle models can lead to higher repair costs. 

• Parts: The cost of the sensor itself generally falls between $20 and $80, but can be less or more depending on the vehicle. 
• Labor: Professional labor costs typically range from $50 to $250. This depends on the accessibility of the sensor; if it's in a hard-to-reach spot, labor will be more expensive. 
• Total Cost: The total repair cost will likely be between $70 and $330. 
• Factors Influencing Cost: The specific make and model of your car is the biggest factor. For example, a 2009 Chevrolet Impala might cost around $192, while a 2015 Jeep Renegade could be closer to $376. 

Can I drive with a bad coolant temperature sensor?

No, you should not drive with a bad coolant temperature sensor, as it can lead to serious and expensive engine damage due to overheating or incorrect fuel mixture. A faulty sensor can cause the engine to overheat, run inefficiently, have poor fuel economy, and trigger a "check engine" light. 
This video explains the symptoms of a bad coolant temperature sensor: 58sMechanic BaseYouTube · Feb 6, 2024
Risks of driving with a bad coolant temperature sensor

• Engine overheating: The sensor provides the engine's computer with critical information about its temperature. If it sends incorrect readings, the computer may not activate the cooling fans, leading to overheating, especially at idle or in stop-and-go traffic. 
• Poor performance and fuel economy: The computer uses the sensor's data to adjust the fuel-air mixture. A bad sensor can cause the computer to think the engine is colder than it is, leading to a fuel-rich mixture that wastes gas, reduces fuel economy, and causes the engine to run roughly. 
• Increased emissions: A fuel-rich mixture from a faulty sensor can lead to increased emissions and black smoke from the exhaust. 
• Transmission issues: The transmission control module may also rely on the coolant temperature sensor's data, which can lead to incorrect shifting or a failure to shift into overdrive. 
• Long-term damage: Consistent overheating or improper fuel mixture can cause long-term damage to internal engine components, which can be very expensive to repair. 

This video explains how a bad coolant temperature sensor can affect the engine: 59s8020 AutomotiveYouTube · Mar 2, 2025
What to do instead

• Get the sensor diagnosed and replaced as soon as possible. 
• If you need to move the vehicle, do so very carefully and for the shortest distance possible, monitoring the temperature gauge closely for any signs of overheating. 

How much is a coolant temperature sensor replacement?

The total cost to replace a coolant temperature sensor typically ranges from $70 to $330, including both parts and labor. The cost depends on the vehicle model and whether you do it yourself or hire a mechanic. The part itself generally costs between $15 and $80, while professional labor adds $50 to $250 or more, depending on the accessibility of the sensor. 
This video explains the symptoms of a bad coolant temperature sensor and the replacement process: 1mMaxTheCarGuyYouTube · Jan 31, 2024
Cost breakdown

• Parts: The sensor itself typically costs between $15 and $80. Some high-end sensors or specific vehicle models might be more expensive. 
• Labor: A mechanic's labor costs can add $50 to $250 or more. The final labor cost is influenced by how difficult the sensor is to access; some can be reached in minutes, while others require more time to get to. 
• Total: The combined cost for parts and labor usually falls between $70 and $330. 

DIY vs. professional replacement

• DIY: If you have basic mechanical skills, you can save money by replacing the sensor yourself. The process is often straightforward and can take as little as 10-30 minutes, depending on the vehicle. 
• Professional: A mechanic can handle the job, but it will be more expensive due to labor costs. The final price depends on the labor rate in your area and the complexity of reaching the sensor. 

You can watch this video to learn how to replace the sensor yourself: 53s8020 AutomotiveYouTube · Mar 2, 2025
Important considerations

• Accessibility: The main factor affecting the final cost is how hard it is to reach the sensor. Some are in plain sight, while others are buried under other components. 
• Coolant: Some coolant will likely be lost during replacement and will need to be topped off, which may add a small cost for new coolant. 
• Potential complications: In some cases, replacing the sensor can be a more complex job involving more parts or time, as seen in cases where the sensor is hard to get to or other issues are discovered, like in the example of the 2009 Prius. 

Is it easy to replace a coolant temperature sensor?

Yes, replacing a coolant temperature sensor is generally considered an easy job for someone with basic mechanical skills, but its difficulty depends on the sensor's accessibility. The replacement itself can be quick, but factors like draining coolant, cleaning up, and testing can make the total time longer. 
This video shows how to replace a coolant temperature sensor: 57sOmegAlpha ConsultingYouTube · Nov 19, 2023
Factors that make the job easy

• Accessibility: If the sensor is in an easy-to-reach location, the job is straightforward and may only require a basic tool like a wrench or socket. 
• Simple process: The basic steps of unplugging the old sensor, removing it, and installing the new one can take as little as 5-10 minutes. 

Factors that can make the job difficult

• Sensor location: Some sensors are difficult to access and may require removing other engine components to get to, increasing the time and complexity of the job. 
• Coolant management: You may need to drain some coolant, which adds a step for preparation and cleanup, and you'll need a container to collect the old fluid. 
• Special clips: Some sensors use a clip to hold them in place, and these can be tricky to remove and easy to lose. 
• Engine components: Some sensors are mounted in a way that requires more than just a socket to remove, like a clip and o-ring on an Explorer 4.0L SOHC. 

You can watch this video to see how to deal with potential difficulties, such as a sensor that is difficult to remove: 56sthedriversseatYouTube · Jan 14, 2009
General steps for replacing the sensor

1. Let the engine cool down completely. 
2. Gain access to the sensor. This may involve removing the engine cover or other components if the sensor is not easily visible. 
3. Release pressure: from the cooling system by carefully opening the coolant reservoir cap. 
4. Unplug the electrical connector: from the sensor. This can be a tight fit, and you may need a small screwdriver to help release the tab. 
5. Remove the old sensor. You may need to drain some coolant before removing the sensor to prevent a large spill. 
6. Install the new sensor. Don't forget to apply sealant if necessary and tighten it with the correct tool. 
7. Reconnect the electrical connector. 
8. Refill the coolant: to the proper level. 
9. Check for leaks: and start the engine to test your work. 
10. Use an OBD-II scanner: to clear any related trouble codes from the car's computer.