An overheating engine can lead to other serious car problems such as engine block and cylinder damage which can be costly to repair or replace. Therefore, you should always address engine trouble as soon as any issue arises.
However, there are cases where the temperature gauge reads hot, but the engine is cool. In these scenarios, it is crucial to identify the cause of the problem and remedy it as it could signal other underlying issues not related to the engine.
Top signs that your engine is overheating
Knowing the warning signs that your engine is overheating can save you from seriously damaging your Car. Your engine can overheat for several reasons. Some of the most common causes of this are mechanical failures such as broken fans or blown head gaskets. Here are other signs why your Car is overheating;
Hot Hood
When the engine is running, you can expect the hood to emit heat and feel warm to the touch. This is completely normal. If, however, your Car’s hood is extremely hot, this could be cause for concern. You should be able to comfortably place your hand on the hood for 10 seconds without burning it.
The Car is making a ticking Noise
If your engine is making an audible ticking noise, your engine oil is failing to lubricate the moving parts sufficiently. When engine oil is overheated, it loses its lubricating properties and behaves more like water than oil. Therefore, at high temperatures, if the mechanical parts of your engine are clacking against each other audibly, you can expect them to undergo wear and tear at a much higher rate than usual.
There is coolant leaking on the Ground
If you notice a puddle of coolant under your car, it could be a sign of a leak somewhere in your cooling system. On the other hand, it also could indicate that your engine has overheated and boiled the coolant within the radiator, causing the overflow tank to release excess liquid to relieve the high pressure created. In either situation, your Car’s cooling system no longer has the correct amount of coolant flowing through the engine, so it will be prone to overheating.
Your Car smells “Hot.”
A distinctive odor is emitted when the engine heats up enough to start burning oil. As the temperature increases, the rubber seals, plastic valves, and bits of resin holding the whole engine together may begin to melt, releasing fumes that you would not normally smell otherwise.
Most people describe this unusual odor as a ‘hot’ smell. It’s also possible that leaking coolant containing ethylene glycol will fill your Car with sweet-smelling but toxic fumes. Any unusual odors are a bad sign and should not be ignored.
There is steam coming from the Hood
Steam billowing out from underneath your hood is sure that your engine is overheating. As soon as you notice, pull over and turn off the engine. Coolant that has reached its boiling point will convert into steam and build pressure within the cooling system. When it escapes from your Car’s radiator cap or coolant reservoir, you will see it coming out from the front and sides of the hood.
Your Car is making thumping Noises
The thermostat in your cooling system controls the valve, allowing the coolant to flow to the radiator, ensuring efficient engine function. If this valve gets stuck, the trapped coolant in the engine block will become superheated. When cold coolant comes into contact with the superheated coolant, you will hear a loud thumping noise coming from the engine area. Getting the thermostat replaced usually fixes this issue.
Reduced Engine Power
An overheated engine may not be able to deliver enough power to keep your car moving at the rate you want it to move. If you sense the power in your engine is lacking, pay close attention to odd smells or noises that can corroborate engine overheating. Keep an eye on the dashboard temperature gauge or light and pull over if you think the engine is struggling.
Note: If you notice one or more of these signs, there is a high chance that your engine is overheating. The wisest thing to do in this situation is pull over as quickly as possible and turn off your engine.
This will allow the engine to cool down naturally and prevent further damage. If you will raise the hood to allow excess heat to escape, remember to do so with caution, as escaping steam can easily burn you.
It is best not to touch anything under the hood until the engine fully cool down. Attempting to check the coolant level will likely result in a bad burn if the pressure has built up from excess heat.
Why is my temperature gauge going up, but the car is not overheating?
Here are some reasons why your temperature gauge goes straight to high even when you are just starting up your Car;
Faulty Temperature Sensor
If the temperature sensor goes bad, it can potentially cause your temperature gauge to read high even if the actual coolant temperature isn’t that high. If the temperature sends a reading to the incorrectly high computer, the computer might adjust the air/fuel ratio much leaner than normal. Ironically, this can cause the engine actually to overheat.
Bad Water Pump
If the water pump fails, the engine will start to heat up quickly when idling. However, you may also find that the temperature returns to normal once the car moves. This is likely because the extra airflow from the car moving at speed compensates for the lack of coolant circulation.
Broken Temperature Gauge
If your temperature gauge is displaying an incorrect reading, there’s a good chance that it’s the fault of the temperature gauge itself. It’s not common for the gauge to break, but it can happen.
Most of the time, your temperature gauge’s reading will be accurate, so it can sometimes be tough to determine whether your engine temperature is getting too high or whether the temperature gauge is acting up.
Clogged Radiator
A clogged radiator is another possible cause of a high engine temperature gauge. Like a bad water pump, a clogged radiator will result in an engine that will heat up when idling but cool off when the vehicle moves at speed.
Your radiator may be clogged if it’s old and rusty, and it can also become clogged if you are using old or poor-quality coolant. Fortunately, if the damage isn’t too bad already, you may be able to solve the problem by flushing your cooling system and filling it up with new coolant.
Signs and symptoms of a damaged temperature gauge
Below are some signs to look out for when your car temperature gauge is high but the engine is cool;
Check Engine Light is ON
One of the first signs of coolant temperature sensor symptoms you will probably notice is that the check engine light will appear on your dashboard. If the computer detects any problem with the sensor’s circuit, it will illuminate the check engine light, indicating that the car needs an inspection. If you see a check engine light on your dashboard, it is time to check the trouble codes with an OBD2 scanner.
Bad Fuel Consumption
A faulty ECT sensor can send a false signal to the onboard computer, resulting in an incorrect air-fuel mixture. For example, a faulty sensor can signal that the engine is cold when it is not, and more fuel will heat the engine quickly. This will cause the fuel economy to drop and decrease the engine’s performance.
Electrical cooling fans won’t turn on
Some cars use the engine coolant temperature sensor to control the electric cooling fans. So you have two separate temperature sensors for the fans, dashboard gauge, and engine management in most cars.
However, if your car has a single sensor, a bad engine coolant temperature sensor may result in your fans won’t start at all.
Black smoke from the exhaust pipe
Due to an incorrect engine temperature signal, the ECU may enrich the fuel mixture to a point where the combustion process becomes difficult. The excessive fuel will burn in the exhaust pipe and produce thick black smoke.
Difficulty Starting the Car
The starting moment is very critical with the amount of fuel getting injected into the engine. If the air-fuel mixture is faulty, you might find your Car difficult or impossible to start.
Overheating Engine
If the fan receives a false signal, the fan might not turn on, causing the engine to overheat. Some vehicles have a separate coolant temperature sensor for the fan, but many cars use the same sensor.
Car Engine Rough Idles
Due to a faulty ECT sensor, the fuel mixture will adjust. Causing the engine to vibrate or shake when the car is at low speed and lead to other power losses. In addition, the engine is very sensitive to wrong air-fuel mixtures at idle.
Slow Car Acceleration
The engine coolant temperature sensor can have a hard impact on the air-fuel mixture. A bad air-fuel mixture can also cause the engine performance to drop drastically.