Engine coolant temperature sensor malfunction can spell trouble to your car as it can lead to multiple issues. That’s why you need to learn its most common symptoms.
Every car has this sensor because it can help the engine to provide its optimum performance.
So in this post, I’ll discuss what this sensor is all about, how it works, and some of the common symptoms of a failing engine coolant temperature sensor.
What is Engine Coolant Temperature Sensor?
Engine coolant temperature sensor or simply called as coolant sensor, is part of the cooling system and an essential component in your engine’s computer system. Its job is to measure the temperature of coolant inside your engine and send that data to your engine control module or ECU.
This ensures that your engine is in the right temperature and not overheating, while also checking the balance of coolant levels. In short, it tells the ECU how hot your engine is.
Based on that definition, coolant sensor plays a crucial role in keeping your engine and your car in general, as reliable as possible.
And because it plays a vital role in engine performance, a failing coolant sensor can inflict great damage to your car if not replaced or repaired.
How does Engine Coolant Temperature Sensor Work?
As mentioned above, the coolant sensor monitors if your engine is overheating or not. If it’s overheating, it will send that information back to the ECU to trigger various ways on how to contain the temperature increase.
This include adjustments on air-to-fuel mixture, continuous engagement of the radiator fan, turning off the AC, and many others.
Heck, some cars even have a failsafe mechanism where the engine will automatically shut off once it reaches a certain high temperature to protect if from further damage.
So you see, if your coolant sensor is bad, it will mean disaster for your car as it can trigger serious engine damage.
That’s why it is quite important to know various symptoms of a bad engine coolant temperature sensor. So what are some signs that can trigger that your coolant sensor may be failing?
Check Engine Light
Sensors are responsible for keeping a car running smoothly and trouble-free. If any of these sensors fail, then it will create a domino effect of bad things for your vehicle. The same goes with engine coolant temperature sensor.
If your coolant is getting hotter beyond a certain point, then your sensor will pick up that data and sends them to the ECU which will trigger your temperature level in your dash to rise dramatically.
However, if your coolant sensor is bad, it won’t trigger temperature level increase warning on your dash, but it will turn your check engine light on.
So the very first sign of a bad coolant sensor would be check engine light.
Overheating Engine
If your cooling system is truly overheating, it will send warning light on your dash and your water level gauge will increase.
However, a bad engine coolant temperature sensor will give your ECU a false reading. This can lead to overheating issue when your engine’s temperature is actually safe. This will trigger a warning light on your dash.
Or, your engine coolant temperature sensor sends signals to your ECU that your engine is in normal temperature, when in reality, it is already overheating.
See the importance of this sensor?
High Fuel Consumption
The coolant sensor isn’t just responsible for reading the coolant flow temperature inside your engine, but it also picks up data for air and fuel ratio. Meaning that the sensor ensures the correct mixture of fuel to be burned.
How does it work?
If your engine has a higher ratio of fuel, it is going to be used to help cool down the engine’s temperature. So when a failing coolant sensor tells the ECU that your engine is cold when in reality your engine is actually hot, more fuel will be used than usual leading to poor fuel economy.
Black Smoke Emission
There are variety of smoke colors that are being emitted by a car exhaust system. There are blue smoke, white, and the infamous black smoke.
But did you know that a bad coolant sensor can also trigger black smoke? Yes, this is another common symptom of a bad coolant sensor
How you ask? Well, just like the aforementioned symptom above, emissions from a vehicle is a result of the air and fuel mixture getting burned.
If too much fuel aren’t burned by the engine, it will result to poor fuel economy. But the effects doesn’t end there. Those excess unburned fuel will get cooked in the exhaust which leads to black smoke.
Summary
There are many other signs that I can share with you when it comes to failing engine coolant temperature sensor, but these fout are the most common and some are already incorporated in the post like irregular temperature readings.
As you now learned, this sensor is a very critical component in your cooling system and to your car as a whole. It can damage your engine once it sends wrong data to your ECU.
So you better know how to diagnose a bad coolant sensor as well.
Good thing is that I have a video on how you can check and diagnose if your engine coolant temperature sensor is going bad. Below is my DIY diagnosis of coolant sensor.
The video is of course in Tagalog language but has English subtitle on it. Enjoy!
Image Credits:
Wikiuser100000
https://commons.wikimedia.org/wiki/File:Vw_engine_check.jpg
