Why does my car lose power in the heat?

He heat Summer doesn’t look good on your car. When the outside temperature exceeds 35ºC, your engine loses about five horsepower (up to 15 HP in some turbocharged engines) and fuel consumption also increases by an average of one liter every 100 km.

They also appear other drawbacks in brakes (they fatigue faster due to overheating), tires (their life is reduced by 15%), the body paint that loses shine and the interior, which tends to discolor and deform. All this is inevitable, but you can ensure that the heat affects your car as little as possible:

Engine intake air too hot

All engines, whether diesel or gasoline, need to introduce air into the cylinders in order to burn the fuel. When the temperature is high, the air contains a lower proportion of oxygen and the mixture does not burn as easily, so engine performance declines. This is seen especially in the turbo engines or with an air compressor (they lose up to 15 HP) since, as these engines need more air to operate, the lack of oxygen affects them more.

You can’t do anything to avoid it, but you will notice a greater loss of performance if you have a dirty engine air filter or the spark plugs with too many kilometers, two cheap maintenance operations.

Overloaded cooling system

The cooling system ensures that the engine does not exceed the normal temperature at which it operates (between 85 and 95 degrees). In summer, especially when you are driving less than 40 km/h, the electric fan has to operate more often and the engine performance drops (around 2 HP). Fortunately, the increase in consumption is negligible.

It can’t be avoided, but if you change the coolant every four years and check its level once a month you will help your car.


Vehicle air conditioning uses a compressor driven by the engine. Therefore, every time it starts, it subtracts a few four horses on average of performance.

You could stop using the air conditioning to avoid this, but the loss of power generated by having it running is so small that it is negligible. The increase in consumption (which exists) is not exaggerated either.

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