Nobody wants to be stranded on the side of the road, waiting for their overheated engine to cool down enough to limp the rest of the way home. Coolant leaks are a frustrating and inconvenient problem that can lead to further engine damage. The good news: sometimes you can spot a coolant leak before it becomes a disaster.

Proper maintenance and thorough inspections are the most effective way to avoid coolant leaks. If you have recently acquired a used or rebuilt title car (sometimes referred to as a restored title car), make sure it undergoes a thorough inspection to check for leaks or cracks that could develop more serious problems down the road.

If you notice signs that your radiator is experiencing problems, it’s best to get it to a trusted mechanic as soon as possible.

Why Does My Car Have a Coolant Leak?


What To Watch For

Leaking Coolant.

A radiator that is losing coolant is the most obvious indicator that something is off. Over time, it is normal for your car to burn off some coolant, but this should amount to 2-3 ounces per year, nothing more. If you find a puddle of coolant under your car or find yourself refilling your radiator reservoir regularly, it indicates a bigger problem.

Watch for a pool of fluid under your car that is bright green and smells distinctively sweet. It’s important to note that coolant leaks should be immediately cleaned up before any pets or children can access it, as coolant is highly toxic.

Rising Temperature Gauge.

Another thing to look for is a rising temperature gauge. It’s normal for the temperature of your car to fluctuate as you drive, but extremely high temperatures indicate something is wrong, and your engine is at risk of being damaged.

Low Coolant Levels.

If you suspect something is amiss with your coolant, checking the levels is easy, and your owner’s manual will tell you exactly how. If you fill your coolant tank and levels become low again, you have an issue that needs immediate attention.

Check Engine Light.

While your check engine light can mean many things, it can indicate that your engine is running low on coolant. If your car senses that the system that protects your engine from overheating is low on coolant, it may trigger your check engine light. Leaving the coolant level low can lead to engine damage so make sure to deal with the check engine light promptly.

What Could be Wrong?

A handful of things could be causing issues in your radiator and cooling system.

Corrosion in Your Radiator.

Over time, the heat and movement of your car’s engine cause normal wear and tear. A hole in the radiator is not uncommon due to the stress on this part of your car. A corroded hole, failing tubes, and sealing gaskets are all reasons you may be losing coolant. If you detect that your hoses or seals are deteriorating, it’s best to proactively replace them, as waiting for them to fail can lead to far more expensive repairs.

Blown Head Gasket.

A head gasket performs a vital function for your engine. When it blows, it exposes the engine’s combustion chamber to coolant and oil, resulting in costly damage and potentially leading to a significant coolant leak. A blown head gasket is a significant problem, and you should stop driving your car immediately if you suspect this is an issue.

Radiator Cap.

Your radiator is under extreme pressure, and any pressure loss jeopardizes the system’s effectiveness. A radiator cap is often the culprit. Over time the seal can deteriorate and wear out, or the spring might become ineffective. If the cap fails, the system fails to pressurize, and you may begin to lose coolant. Luckily, a radiator cap is a quick and easy fix.

Expansion Tank.

The expansion tank is the part of your radiator that you add coolant to. It comes into play as the system heats and cools, allowing for expansion that comes with pressure changes. Over time the expansion tank is exposed to extreme temperature changes. The wear and tear can lead to cracks in the plastic reservoir or hoses, leading to a loss of fluid.

Water Pump.

The water pump moves coolant through your car’s system to ensure your vehicle is running at optimal temperatures. Coolant will no longer flow through your engine if the water pump fails or develops a leak, causing heat issues.

Preventing Coolant Leaks

While there are no guarantees in the world of car mechanics, the best way to avoid a coolant leak is through routine maintenance. A trained professional can often spot leaks, cracks, and compromised parts of the radiator system.

Do You Have a Coolant Leak?

If you have a coolant leak, it is important to have your car repaired by a professional as quickly as possible. Initial repairs of leaks and seals are relatively inexpensive, but if they are left unchecked, they will lead to hefty repair bills later on.

It is best not to drive a car with a coolant leak, as any driving may lead to more damage. If you need to try and drive a few miles to a mechanic, top off the coolant right before you leave, keep an eye on the temperature gauge, and stop immediately if your car begins to overheat.