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Why Does My Car Overheat In Traffic?

causes of overheating car

Car overheating is usually caused by hot weather whilst other vehicle components are failing. If the vehicle is overheating in “average” weather, you will have a problem with the cars cooling system that will need to be investigated.

However, the vehicles thermostat could be broken causing abnormal readings. Clearly, you cannot remove this part on the side of the road therefore be cautious and check it once the car has cooled down.

Table of Contents

What Causes A Car To Overheat In Normal Weather?

  • The coolant and water level is too low within the car radiator
  • Coolant leaking internally or externally
  • Broken thermostat providing abnormal values
  • Electric cooling fan is not fully functional
  • Faulty fan clutch
  • Water pump leaking
  • Blocked catalytic converter
  • Low engine oil
  • Aggressive/overworking the engine

What To Do If Your Car Overheats And You Can’t Stop?

Sometimes you may find yourself driving with no safe place to pull over. This means the tactics to help your car cool down are different to when you can stop whilst overheating.

If your vehicle is overheating and you cannot stop the car, follow these steps:

  1. Turn the heater to full heat and fan at full power. This helps transfer heat out from the engine, therefore you may want to open the windows otherwise you will overheat too.
  2. Turn of air conditioning. Using air con puts additional stress on the engine to power the compressor. This is something you want to avoid.
  3. Turn off engine whilst standstill. If it is safe to do so, turn of the engine and then turn the key into the second last position to resume the radiator and cooling functionality. This will aid the cooling process whilst the engine isn’t on.
  4. Drive gently. Driving fast and then stopping quickly is not the answer. Gradually picking up speed whilst keeping the RPM to the minimum and coasting to a stop whilst allowing as much air as possible to the engine.
  5. Avoid major traffic. If its possible to take a different route that will be avoiding the traffic. This will allow for higher speeds and more air flow to the engine. If this is not possible and you are heading for rush hour traffic, its best to find a place to stop for the health of your car engine.

steps to cool down a car when its overheated

If you are car is overheating and you can pull over to the side, you will be able to open the bonnet. Avoid touching the engine because as you would imagine, it will be way too hot to touch.

Do not open the radiator cap as this will be under a lot of pressure that will result in steam or liquid bursting from the exit. You should check the coolant level of the reservoir tank and top it up with some quality coolant if it is not at the recommended level. Most cars will have a mark on the container of where the coolant should be topped up to.

Whilst the bonnet is open, if you spot a leak from the radiator or cylinder head, you should consider whether to carry on your journey. If you are embarking on a hundred mile journey, it is probably best to turn round and go back home.

If your journey has only a few miles left, let the car cool down and drive to the destination once cooled down. We highly recommend purchasing a radiator stop leak, which will allow you to temporarily solve the issue of leaking coolant.

However, if your car has low coolant, the temperature of the engine will rise very quickly, so you may need to be tailored home.

It is not worth causing serious damage to your engine from low coolant, so ensure that you can pour more coolant before embarking.

What Are The Consequences Of A Car Overheating?

Its important to fix a problem before it has chance to become much worse. Prevention will also be cheaper than repairing damaged parts and checking your coolant levels regularly is critical. The problems that can occur from a car that overheats regularly are a cracked head gasket, warped cylinders and more.

The purpose of a head gasket is to prevent anti freeze from leaking. A cracked head gasket will allow coolant anti-freeze to leak into the engine and once cracked, it is a time consuming job to complete.

Cylinders can also become warped from the anti-freeze leaking into the cylinders themselves. They degrade and warp, causing the engine to require major work or even a brand new engine.

Symptoms That Your Car Will Overheat

Prevention will be part of the major car service when you change/check the coolant level. However, if you drive an older car or a neglected car that has not been serviced, it is important you understand the symptoms.

Steam or smoke is the most common symptom of a overheating car. It could be oil in the exhaust or it could be much worse, such as an overheating engine. On the topic of oil, low levels of it will cause overheating. Always use high quality synthetic motor oil when servicing your car.

Most modern cars will have a thermostat that will flash constantly if the car is dangerously overheated. This should not be ignored, however if the engine is cold and the error remains, you may need to clear the error code with an auto scanner.

Another common symptom is hot air from the air conditioner but this can be resolved with topping up the coolant. After reading these three main symptoms, you should be aware of the potential issues that are common with overheating cars.

procarreviews author

Written By Dan

About the Author

Dan is an automotive journalist and owner of over 10 cars ranging from supercars, tuned cars, classics and your good old beater cars. He always likes to get his hands dirty with nut and bolt restorations or detailing sessions using the best products on the market.

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