Asked by: Qiuhua Zucar
automotive auto repair

What happens if the coolant temperature sensor is bad?

Last Updated: 4th January, 2020

19
If the coolant temperature sensor goes bad it can send a false signal to the computer and throw off the fuel and timing calculations. This will cause the computer to think the engine is cold, even when it is not, and as a result will use more fuel than necessary.

Click to see full answer.

Moreover, what are the signs of a bad temperature sensor?

Common symptoms of a bad engine coolant sensors are overheating, hard starting conditions, poor idle, check engine light ON and the electric fans do not work properly. The easiest way is to read the trouble code memory and check the value from the sensor, to make sure it's a possible value.

Likewise, can a bad coolant temperature sensor cause car not to start? If the sensor is reading too high of temperature when compared to the ambient air temperature sensor when first started then the computer would see it as a problem and turn on the check engine light an go into failure management mode and use a known good reading. The sensor will not cause a no start.

Correspondingly, can you drive with a bad coolant sensor?

Anyone with specific knowledge weigh in. Usually the Coolant Temp Sensor is used for the gauge for fuel trims for cold start enrichment, and fan control. Since the Thermostat and water pump are mechanical the engine will still cool. you will be fine driving until the replace the sensor.

What does the coolant temperature sensor do?

A coolant temperature sensor (CTS) (also known as an ECT sensor or ECTS (engine coolant temperature sensor) is used to measure the temperature of the coolant/antifreeze mix in the cooling system, giving an indication of how much heat the engine is giving off.

Related Question Answers

Evert Essid

Professional

What will a bad coolant temp sensor do?

Coolant Temperature Sensor Test. A bad engine coolant temperature sensor affects engine performance: It may cause a constant lean air/fuel mixture, causing the engine to stall or idle rough. Or it may cause a constant rich air/fuel mixture, causing an increase in emissions and fuel consumption.

Roy Schliwinski

Professional

Where is the cooling fan sensor?

The cooling fan relay is normally located in either the underhood fuse and relay center or mounted to the electric fan assembly behind the radiator.

Anunciada Hadrich

Explainer

Does the coolant temp sensor control the fan?

The sensor works by measuring the temperature that's being given off by the thermostat and/or the coolant itself. The temperature is then sent to the on-board control system. As the control system receives the temperature from the CTS, it may trigger the cooling fan to either shut off or turn on.

Thomasina Capinha

Explainer

Where is my coolant temperature sensor located?

The Engine Coolant Temperature Sensor is located in the coolant flange to the left of the cylinder head and is integral with the ECT sensor. The Engine Coolant Temperature Sensor is located in the coolant pipe, below the air intake pipe and behind the right cylinder head and is integral with the ECT sensor.

Hermenegildo Raventos

Explainer

How do you fix a coolant sensor?

Replacing this sensor is an easy project that can be done in your own garage or on a flat driveway.
  1. Step 1 - Open Car Hood.
  2. Step 2 - Locate Coolant Temperature Sensor.
  3. Step 3 - Remove Lead Wire from Terminal.
  4. Step 4 - Loosen Coolant Sensor.
  5. Step 5 - Remove and Replace.
  6. Step 6 - Torque Sensor in Place.
  7. Step 7 - Reconnect Wire.

Arkadiy Mladentsev

Pundit

How do you change a coolant temperature sensor?

How to Replace a Coolant Temperature Sensor
  1. A video of this job being done is at the bottom of this guide.
  2. Release the Cooling System Pressure.
  3. Locate the Coolant Sensor.
  4. Remove the Electrical Connector.
  5. Remove the Coolant Sensor.
  6. Install the New Coolant Temperature Sensor.
  7. Refill the Cooling System.

Samir Fellerman

Pundit

How do I know if my coolant temperature sensor is bad?

Signs Your Engine Coolant Temperature (ECT) Sensor Is Bad
  1. Your check engine light is on: If the engine's computer detects a problem with the coolant temperature sensor, or its circuit, it will turn on the check engine light.
  2. Your engine stalls: When the engine is first started, it will require more fuel in order to idle smoothly until it's warmed up.

Mateos Lubberstedt

Pundit

How much does it cost to replace coolant temperature sensor?

The average cost for an engine coolant temperature sensor replacement is between $148 and $193. Labor costs are estimated between $82 and $105 while parts are priced between $66 and $88. Estimate does not include taxes and fees.

Evodia Litman

Teacher

What is the difference between a coolant temperature sensor and sender?

But a SENDER can be anything that sends a signal such as a telegraph sender. A SENSOR detects something such as temperature, pressure, light, etc. and generates a signal (which can be sent).

Lindsay Lepthin

Teacher

Can a bad coolant temp sensor cause misfire?

Overheating engine
The coolant temperature sensor can also fail in a manner that causes it to send a permanently hot signal. This can cause the computer to incorrectly compensate for a lean signal, which can result in overheating, and even misfires or engine ping.

Hyun Reihsig

Reviewer

Should radiator fan run all time?

An electric fan SHOULD NOT run all the time. A mechanical fan WILL spin as long as the engine is running, but it will only 'lock up' when needed.

Alexsandra Johnston

Reviewer

Can overfilling coolant cause overheating?

Too much coolant can cause significant problems to your vehicle. Overheating, as previously described, corrosion, water pump failure and increased engine wear. In some instances, for example in very moist and hot temperatures, lack of coolant can also cause your engine to overheat.

Nere Joannes

Reviewer

What sensor causes a car not to start?

If the problem is no spark, anything in the ignition circuit that creates the spark may be at fault. Use your AutoTap Express DIY to look for an RPM signal from the Crankshaft Position sensor while cranking the engine. A bad Crankshaft Position sensor is a common cause of no starts.

Maverick Awzaloff

Supporter

Can a bad coolant temp sensor cause rough idle?

A faulty coolant sensor that always reads cold may cause the fuel control system to run rich, pollute and waste fuel. A coolant sensor that always reads hot may cause cold driveability problems such as stalling, hesitation and rough idle. This also affects engine performance and fuel economy.

Jenette Ropero

Supporter

Can a bad sensor prevent a car from starting?

Since any engine requires the correct air to fuel ratio and ignition timing to start, having a faulty sensor that can't adjust these symptoms on the fly can cause the engine to not start. Dirty sensors will impact whether your vehicle starts. An example of this is the Mass Air Flow sensor or MAF.

Presentina Oldemanns

Supporter

Would low coolant keep car from starting?

Having no coolant in your engine can kill it very effectively if driven like that for any substantial amount of time and in many of the newer models of vehicles, it will tell your car not to start until it full of coolant, to prevent break down.

Faly Petrisor

Beginner

Can you drive with a bad temperature sensor?

Anyone with specific knowledge weigh in. Usually the Coolant Temp Sensor is used for the gauge for fuel trims for cold start enrichment, and fan control. Since the Thermostat and water pump are mechanical the engine will still cool. you will be fine driving until the replace the sensor.

Zeina Welt

Beginner

What happens if you unplug the coolant temp sensor?

Plugged in, the sensor is sending a signal for an extremely cold setting, with a very rich mixture as the result. Disconnecting the sensor may be getting you a default setting, and fuel mixture, that is much better for the engine's performance.

Silvestra Rosario

Beginner

What does engine coolant temperature sensor do?

A coolant temperature sensor (CTS) (also known as an ECT sensor or ECTS (engine coolant temperature sensor) is used to measure the temperature of the coolant/antifreeze mix in the cooling system, giving an indication of how much heat the engine is giving off.