When your car’s temperature gauge starts creeping into the red, it’s not something you can ignore. An overheating engine can cause major damage if not addressed quickly. But what causes a car to overheat in the first place? Let’s dive into six common reasons—and what you can do to fix them.

1. Low or Leaking Coolant

Why it happens: Coolant (antifreeze) is essential for regulating your engine's temperature. If your coolant level is low due to a leak or evaporation, your engine can overheat.

How to fix it:

• Check the coolant reservoir under the hood. If it’s low, top it off with the correct coolant type for your vehicle.
• Look for puddles under your car—this could indicate a leak.
• If you're frequently adding coolant, you may have a bigger issue that needs professional attention.

2. Failing Thermostat

Why it happens: The thermostat controls the flow of coolant through your engine. If it gets stuck closed, it can prevent coolant from circulating properly, causing overheating.

How to fix it:

• A faulty thermostat needs to be replaced. If your engine is overheating quickly after starting, it’s time for a visit to All-Star Automotive Repair.

3. Malfunctioning Radiator or Radiator Fan

Why it happens: The radiator cools down your coolant before it recirculates through the engine. A damaged radiator or a broken fan can’t cool efficiently, leading to overheating.

How to fix it:

• Check for visible leaks or blockages in the radiator.
• Make sure the radiator fan is turning on when the engine heats up. If not, the fan motor or sensor may need to be replaced.

4. Broken Water Pump

Why it happens: The water pump moves coolant through the engine. If it fails, your car can overheat quickly.

How to fix it:

• A mechanic can check for leaks or a failing pump. If your water pump is faulty, it needs replacement.

5. Clogged or Blocked Cooling System

Why it happens: Over time, rust, debris, and old coolant can clog the system, preventing coolant from flowing freely.

How to fix it:

• A coolant flush can help remove buildup and keep your system running smoothly.

6. Blown Head Gasket

Why it happens: A blown head gasket allows coolant to leak into the engine, causing overheating and even engine failure.

How to fix it:

• If you notice white smoke from the exhaust, bubbling in the coolant reservoir, or milky oil, you may have a blown head gasket. This is a serious repair that requires professional service.



What to Do If Your Car Overheats

If your car starts overheating while driving:

Pull over immediately and turn off the engine.
Let the engine cool down before opening the hood.
Check coolant levels if it’s safe to do so.
Call a trusted mechanic if you’re unsure what’s causing the issue.

Ignoring overheating issues can lead to severe engine damage. If your car is running hot, bring it to All-Star Automotive in Columbia for a full diagnosis and expert repair.