What to Do If Your Car Overheats

By Andy Jensen on August 21, 2020 in life hacks

Who doesn’t love summer? The weather’s excellent, outdoor activities are aplenty, and kids enjoy being out of the classroom for three months. But while the kids pretend the floor is lava, your car engine may also try to become lava.

As summer temperatures rise, so does the chance your engine will overheat. Overheating is a sign of serious malfunction, and it could be dangerous and expensive if you handle it incorrectly. Keep reading to understand warning signs that your engine is getting too hot. Then discover why it may be overheating and what to do if it is!

Signs Your Car is Overheating

An overheating engine needs your immediate attention, and fortunately it gives some warning signs.

• Rising temperature gauge

Check your gauges occasionally as you drive. Your engine probably runs warmer in summer, but if you see the needle slowly creeping to the red zone, that’s a hint something’s wrong. A check-engine light should also come on when it gets too hot.

• Steam under the hood or a strange smell

Rolling steam from under the hood is a classic indicator of car troubles in movies, and it’s also true in the real world. Engine coolant is mostly water and alcohol, so a coolant leak onto hot engine parts will evaporate the mix and send up clouds of sweet-smelling white steam.

• Thumping or ticking engine

We all know these are not great sounds. Ticking usually means the oil is too hot and too thin to protect the engine parts from clattering together. Thumping noises mean the coolant in the engine is super-heated, causing a rapid expansion in the cold coolant when they mix. Another sign of an excessively hot engine is a pinging sound caused by fuel igniting too early, a symptom called pre-ignition that can cause expensive engine damage.

Why Cars Overheat

An engine usually operates in a normal heat range. An overheating engine may stem from one of these root problems.

• Low coolant level

Coolant does what its name suggests, primarily, it keeps the engine cool. It cools by circulating a liquid through passages in the engine. The fluid collects heat and flows to the radiator, where air carries the heat away. When the coolant level is low, there isn’t enough liquid to effectively pull heat away from the engine. Coolant can even boil off in extreme situations.

• Low oil level

Without oil to lubricate moving parts, your engine would quickly turn into the world’s most inefficient metal lathe, grinding each part against one another until the engine fails. While oil is primarily a lubricant, it also plays a role in cooling. Even running a quart low on oil will dramatically increase engine heat.

• Coolant system leak

Coolant can leak from the radiator, coolant hoses, head gasket, water pump, and every place in between. A leak will eventually cause the previously mentioned problems stemming from low coolant.

• Broken thermostat

You can think of a car thermostat as a simple open/closed valve in the cooling system. On engine start, the valve is closed, so the coolant stays in the engine passages, warming it up. Once the engine nears operating temperature, the thermostat opens, allowing normal circulation of the coolant. If a thermostat is stuck closed, your car will overheat in much the same way as when you don’t have enough coolant.

What to Do If Your Car is Overheating

If your temperature creeps up or you notice other warning signs of an overheating engine, take these steps.

1. Turn off the air conditioning

The air conditioner uses engine power to condense and cool the air for your cabin. By turning off any extra work the engine has to do, engine temperatures could drop.

2. Blast the heater

It may sound unbearable in summer but give it a try for a few minutes. With the heater blowing, you remove excess heat from the engine bay. If you’re a little low on oil or coolant, this trick could get you home safely.

3. Pull over

If the temperature gauge doesn’t go down, it’s time to stop. Remember that expensive engine thumping mentioned above? Avoid that by finding a place to park and shutting off the engine as soon as possible. Bonus points for a shady spot!

4. Don’t open the hood

It’s blazing hot under there right now, so give it at least 30 minutes until you carefully try to open it. Then give it another 30 minutes before you touch anything.

5. Check the coolant level

Use a heavy work glove, old shop rag, or even a towel to protect yourself from escaping steam or hot coolant. Pop off the radiator cap, and you should see coolant nearly filling it. If it’s more than a few inches low, you may have found the problem.

6. Look for leaks

Check under the radiator and coolant hoses for drips. Also, look for cracked or swollen hoses. A big leak under the engine may mean you have a failed water pump. Carefully place a hand on the upper radiator hose. If it’s cold when the engine is warm, you may have a broken thermostat. Also, while you’re looking, check the oil level and make sure it isn’t low.

7. Add more coolant

If you’re near an auto parts store, grab your specific manufacturer’s brand of coolant. If you pulled over at a gas station, grab their generic coolant mix. If you’re stuck at a grocery store, distilled water works great, and it’s cheaper. Straight water in the radiator works for NASCAR, but it’s better to add proper coolant for its antifreeze and anti-rust properties.

8. Drive and monitor heat

Go for a test drive, and monitor your engine’s temperature. Repeat the above steps if necessary.

9. Take it to the shop

If you haven’t solved your issue, you need a mechanic. An overheating engine could mean you need an expensive head gasket repair, but it could also be something inexpensive such as a $10 radiator cap. Regardless of the price, an overheating vehicle is too dangerous to drive.

Conclusion

If you drive when it’s blazing hot outside, occasionally glance at the engine heat level. If you notice the temperature rising, try the tips above. Save the headache and expense of engine damage by repairing an overheating engine as quickly as possible.