Overheating Engine: Why It Happens and What to Do if Your Car Is Overheating

Who wouldn’t be frustrated and scared to see smoke coming from under the hood as they’re out on a summer drive? Overheating engines can and do happen, and the damage can be permanent if the right precautions and actions aren’t taken. Engines that run too hot can cause damage and ruin your journey.

Goodyear Auto Service is here to help you understand why engines overheat, plus, possible actions to take if your vehicle begins overheating while you’re driving.

If you are in a vehicle that is overheating, do not try to drive farther. Pull over, stop driving and turn the vehicle off. Actions can be taken to assess any issues, though the best course of action is to have the vehicle towed to your nearest Goodyear Auto Service.

Before getting into reasons why an engine can begin to overheat, it’s good to understand what an engine’s cooling system does. The overall cooling system keeps a standard operating temperature for the engine by circulating coolant, or antifreeze, through the engine to the radiator, thus pulling heat away from the engine.

Today’s engines are typically built to be durable, but when heat generated by a vehicle’s motor is well above the normal operating temperature, the devices made to cool this heat distribution may begin to fail, potentially causing permanent damage to not only the engine, but also the gaskets, hoses and seals that are designed to keep the engine running. 

There are a variety of reasons that a vehicle can overheat, such as cooling system leaks, blocked hoses from corrosion and mineral deposits, radiator issues or broken water pumps. Regular inspections may help avoid overheating issues down the road.

As soon as you notice an issue with your vehicle, the next course of action is to pull off the road to a safe and clear area and turn off the vehicle. If the vehicle is overheating, continuing to drive with a potentially damaged engine may cause permanent damage.

If there is a situation where you are not able to come to a complete stop in a safe and clear area, keeping the vehicle slowly moving may still allow a constant airflow around the motor to help aid in natural cooling. Leaving your car at rest with the engine running may worsen the problem, which can quickly produce additional and unwanted heat.

Yes, that’s right. When the vehicle is still in motion, turning off the air conditioning and increasing the heat to high may help to pull additional heat away from the engine.

The goal is to release as much heat as possible. Rolling down and opening as many windows as possible is another way to allow heat to flow out of the vehicle.

Once the vehicle is at a complete stop and turned off, do not lift the hood. Depending on how long the vehicle has been running, the coolant in the vehicle could be increasing in temperature to an extremely hot level, and essentially pressurizing in the cooling system itself. Only once the vehicle has completely cooled down will it be suitable to attempt to open the hood. The vehicle should be allowed to cool down naturally before opening the hood.

To confirm that the vehicle has appropriately cooled down, monitor the temperature gauge in your vehicle as it moves from HOT to COOL, which may take upwards of 30 minutes. Depending upon the vehicle you drive, the temperature gauge may only be functional when the ignition is in the “accessory” or “on” position. During this step, it’s important to not start the engine, and in this situation, only activate the ignition to the “on” position to read the temperature gauge.

There are a variety of reasons why a vehicle’s engine can overheat. Certain examples may be quicker fixes, such as refilling your antifreeze, but other issues may be more permanent if not properly taken care of by a professional.

Below are common factors that can cause a car to overheat:

Driving without proper levels of coolant/antifreeze may cause a coolant system failure. If coolant levels are lower than the manufacturer’s recommendation, refill or top off the levels with new coolant/antifreeze. When adding new coolant to an empty reservoir use only a 50/50 mix of antifreeze/coolant and water. If you are unsure where the coolant reservoir tank is located, or the proper method for refilling it, refer to your vehicle owner’s manual.

The water pump’s job is to circulate the coolant throughout the engine. If the coolant is dirty or has too much buildup, it can stop the coolant from moving through the pump, which can lead to an overheating situation.

Radiators and their fans help to reduce heat from the engine by decreasing coolant temperatures. Issues with the fans may reduce the capability of the radiator to remove heat, which will cause unnatural temperature increases.

Outside of lubricating the engine’s parts, a vehicle’s motor oil helps control overall temperatures. Low oil levels may increase engine temperatures.

Like the thermostat in a home, the thermostat in a vehicle is needed to regulate engine temperatures. A thermostat failure may cause harm to the engine by not allowing the coolant to flow as intended by the vehicle manufacturer.

If coolant hoses are leaking, blocked or ruptured, or if the belts are worn out or frayed, their purpose of maintaining air and coolant flow to and from the engine and related systems will be limited and may lead to unexpected engine damage. For more information, view our services on Belts & Hoses.

Coolant flow may be compromised if the engine’s heat exchanger unit is clogged or blocked, which can cause overheating in a vehicle’s engine.

Remembering a few quick tips as you drive can help to alleviate permanent engine damage down the road.

• Check your vehicle’s coolant levels on a consistent basis
• Store an extra bottle of new antifreeze and a gallon of water in your trunk
• Monitor your car’s thermostat as you’re driving
• Do not overuse the car’s air conditioning on extremely hot days 
• Help cool the engine by running the heat at the first sign of overheating 
• Refer to the vehicle owner’s manual to stay up-to-date on coolant service flushes

An overheating engine is a sign of a serious issue. Regular maintenance checks will help identify problems early on, before causing permanent damage to your vehicle. If you have questions regarding your coolant and cooling systems, we’re available to help you at your local Goodyear Auto Service location.