Car Overheating: 8 Common Causes and What to Do

Engine Overheating Is a Serious Problem

When your temperature gauge creeps into the red zone or that warning light comes on, you're facing a potential engine emergency. Overheating can cause severe and expensive damage to your engine, including warped cylinder heads, blown head gaskets, and even complete engine failure.

Warning Signs Your Car Is Overheating

Temperature gauge in the red zone
Steam coming from under the hood
Sweet smell (coolant leaking)
Hood feels unusually hot
Reduced engine power or rough running
Coolant puddles under your car

8 Common Causes of Engine Overheating

1. Low Coolant Level

The most common cause of overheating is simply not having enough coolant. Coolant (a mixture of water and antifreeze) absorbs heat from your engine and dissipates it through the radiator.

Solution: Check your coolant level when the engine is cold. If it's low, top it off and look for leaks.

2. Coolant Leak

If you're constantly adding coolant, you have a leak somewhere. Common leak points include:

Radiator hoses
Water pump
Radiator itself
Heater core
Head gasket (internal leak)

Solution: Have a professional locate and repair the leak.

3. Faulty Thermostat

The thermostat regulates coolant flow between the engine and radiator. When it fails in the closed position, coolant can't circulate, causing rapid overheating.

Solution: Thermostat replacement is relatively inexpensive ($150-$250 with labor).

4. Broken Water Pump

The water pump circulates coolant through your engine. When it fails, coolant stops flowing, and your engine overheats quickly.

Signs: Coolant leak near the front of the engine, whining noise from the pump area.

Solution: Water pump replacement ($300-$750 depending on vehicle).

5. Radiator Problems

Your radiator can fail from:

Clogs: Internal deposits blocking coolant flow
Leaks: Corrosion or physical damage
Bent fins: Reducing airflow

Solution: Radiator flush, repair, or replacement.

6. Failed Radiator Fan

The radiator fan pulls air through the radiator when you're stopped or moving slowly. If it fails, your car may overheat in traffic but run fine on the highway.

Solution: Fan motor or relay replacement.

7. Clogged or Damaged Hoses

Coolant hoses can become clogged with deposits or develop cracks and leaks over time.

Solution: Hose inspection and replacement as needed.

8. Head Gasket Failure

A blown head gasket allows coolant to leak into the combustion chamber or oil passages. This is the most serious and expensive overheating-related repair.

Signs: White smoke from exhaust, milky oil, bubbles in coolant reservoir.

Solution: Head gasket replacement ($1,000-$2,000+).

What to Do If Your Car Overheats

Step 1: Turn Off the A/C and Turn On the Heat

This transfers heat away from the engine. Yes, it's uncomfortable, but it can save your engine.

Step 2: Pull Over Safely

Find a safe spot to stop as soon as possible. Turn on your hazard lights.

Step 3: Turn Off the Engine

Let the engine cool for at least 15-30 minutes before opening the hood.

Step 4: DON'T Open the Radiator Cap

The cooling system is under pressure when hot. Opening the cap can cause severe burns.

Step 5: Check Coolant Level (When Cool)

If coolant is low and you have some available, add it carefully.

Step 6: Call for Help

If you can't identify and fix the problem, call for mobile mechanic service or a tow.

Preventing Overheating

Check coolant level monthly
Flush cooling system every 30,000 miles
Replace coolant hoses every 4-5 years
Watch your temperature gauge regularly

Mobile Cooling System Service in NYC

NYC Mobile Auto Assist offers complete cooling system diagnosis and repair at your location throughout the five boroughs. We can diagnose overheating issues, replace thermostats, water pumps, hoses, and more.