4 Symptoms of a Bad Thermostat

These 3 symptoms of a bad thermostat can cause major problems. The thermostat is an important part that controls the temperature of your engine. Temperature is something that will make your engine run well or can blow it up.

Normal engine temperatures will help keep your engine running in optimal condition but abnormal temperatures will either make your engine really hard to start or cause engine damage due to overheating.

The Symptoms

1) Overheating

Overheating is a problem that is feared by every car owner because it will give your engine with very fatal consequences. Overheat can occur if the cooling system on the machine does not work properly, including thermostat that can no longer open perfectly. Do not remove the Thermostat, because it will disrupt the working temperature of the engine as well as lead to more fuel consumption & volatile coolant.

2) Underheating

Under heating can occur when the thermostat valve is in a tenuous state (open or slightly exposed). The open valve causes the coolant to continue flowing so that the engine temperature will drop. This condition will make the use of your coolant to be very wasteful. Under heating can also cause the machine to be very difficult to turn on or (if it can live) will not be smooth / choked. The stagnant engine will make the machine work very heavy and incomplete combustion. This condition is certainly not good for the engine and your comfort and safety. Stalled engine rotation, if kept allowed, makes your car engine dead at any time. The machine can die by itself either when the car is stationary or when it is running.

3) Fluctuating Temperature

This condition occurs when the engine condition is not too bad and the thermostat damage has not been too long. For some people may not be too concerned with fluctuate temperature because in many cases the car will still run as usual; Like no interruption. This is actually the initial effect of thermostat damage that if left unchecked will certainly worsen the condition of your car engine. This condition can easily be known through the temperature indicator on your car. Needle indicator and temperature indicator light will show unusual activity. Some people may think this is just a temperature indicator breakdown (in some cases it is true), but if both indicators (needles and lights) show strangeness then you should check your car immediately, because this peculiarity may be caused by damage to the thermostat.

4) Bad Engine Performance

Broken or malfunction thermostat will obviously decrease the performance of your car engine. The car engine ideally works well at a certain temperature; Not too hot and not too cold. Overheating machines can cause great degradation on the engine, while the engine is too cold will hamper the performance of your car engine. Neither overheat nor under heat equally do not produce good combustion so engine performance will obviously drop.

Read also: 3 Symptoms Of a Bad Oil Control Vave


Regular checking is the wisest step that car owners should take. You should also know (at least a little) about the important things about your car. You should also understand what the temperature indicator of your car indicates. Coolant checks should also be frequent and never use water as a coolant because the coolant is a liquid that is specially made to cool the engine temperature of the car which may be caused by 3 symptoms a bad thermostat valve.

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