How Long Can I Drive with Low Coolant?

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How Long Can I Drive with Low Coolant?

Proper car maintenance is the primary responsibility of every car owner. When inspecting your car, never ignore the engine coolant. Unlike the fuel that you have to add more often, a coolant takes years before you add. But, once the leak occurs, the engine will have a low or no coolant at all.

So, what’s a coolant, and why is it vital? It could be you are a new car owner or intend to own one soon and have never heard of a coolant. Note that, once ethylene glycol is mixed with distilled water, you get a coolant. Maybe you’re wondering, how long can I drive with low coolant? First, know the importance of the coolant.

Importance of a Coolant

Heat Absorption

Remember, a running engine produces extreme temperatures that can damage internal components. Most of that heat gets out through the exhaust system of the engine. Unfortunately, the heat that remains can cause severe engine damage if not regulated well. That’s why the coolant comes in handy. The coolant circulates your engine, absorb excess heat, and transfer it to the radiator for cooling. It regulates the heat and protects your engine from melting down or suffering severe damage.

Freeze Protection

Have you ever thought about the impact of winter on your car engine? Freezing water causes some engines to expand, and the pressure may damage vital engine components. That’s why you should avoid using water as a coolant. Luckily, using excellent coolant adds anti-freezing protection to your car, thus protecting engine damage.

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Should You Change The Coolant?

You don’t have to change the coolant more often unless your car has a leakage. So the car may take up to five years for you to change it. If it exceeds the manufacturer’s recommendation, it may have electrolysis. As a result, it becomes acidic. Instead of protecting your engine, it starts to erode it. To avoid that, you should periodically flush the engine system and don’t fail to add new coolant.

How Does Leakage Occur?

External Leak

Do you suspect that there is an external leak? You can quickly inspect and fix it. Check if the hose has a crack or is worn out. That may cause the coolant to seep through. If it’s okay, check the condition of your water pump and the heater core. You can also check if the engine freeze plug is okay. If any of those components have an issue, the coolant could easily leak through it.

Internal Leakage

If your car has an internal leakage, you may not notice it by observing. You will only realize that the coolant level is dropping quickly. Your mechanic should check the head gasket since it could be causing the leakage.

The Radiator Cap

A weak or leaky radiator cap can allow the coolant to escape through it. If the radiator cap is the problem, talk to your mechanic. He can also check if the radiator cap is fitting well and fix the problem.

Dangers of Driving A Car That Has A Low Coolant

So, back to the question, is it safe to drive with low coolant? Having known the importance of coolant, you shouldn’t risk driving a car that has either low or no coolant at all. You don’t want to damage the engine. To understand better, here is what will happen if you drive a car when the coolant is low.

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Effects of A Low Coolant 

1. Engine Damage

The coolant regulates the temperature of the engine. Once the coolant gets too low levels, it will not manage to transfer the temperatures. As a result, driving a low coolant car can cause severe damage to vital engine components such as pistons.

2. Blow A Head Gasket

You also risk blowing the head gasket. The signs of blown head gaskets include power loss, the sound of an engine knock; you will also see some smoke from the tailpipe. Your car will also reduce its efficiency.

3. Engine Shut off

It’s dangerous to drive with a low coolant since the engine may shut in the middle of a highway. That may result in an accident. It can also be inconvenient if you are in a hurry, and the engine refuses to start.

So, to answer your questions on how long can you run an engine without coolant? The answer is simple: don’t exceed 15 seconds.

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Symptoms of Low Coolant

Different cars produce different symptoms when the coolant is low. Some of the common symptoms include;

High-temperature gauge reading red

On the dashboard, the gauge should remain between the H and C symbol. Once the gauge indicates that the temperature is high and goes to red, stop the car immediately. Call the mechanic or add the coolant first and also fix the leak.

Malfunctioning AC System

Are your AC vents producing hot air? That may be a symptom of low coolant. That means you need to check the level of the coolant and fix any leakage.

Faulty Coolant Level Sensor 

Once the coolant gets low, the coolant light will turn on. There is a probability that the coolant level sensor is faulty and not necessarily that the coolant is low.

Sweet-Smelling Odor

Are you getting a smelling odor from the hood and the air conditioner? It is possible that your car has a low coolant. You need to consult your mechanic to know what the problem could be.

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A coolant is a vital fluid in your car engine that you should never ignore. It helps to regulate the temperature and also prevents freezing. Though you don’t have to change it regularly, you should ensure that you flush the system and change it periodically. Avoid driving your car when the coolant is low to avoid severe engine damage. You need to know the causes of leakages to help know when a coolant leak occurs. Low leakage symptoms include a high-temperature gauge reading red, a malfunctioning AC, a faulty coolant level sensor, and a sweet-smelling odor. The mechanic can fix the leak.

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