How to Start a Car Engine in Cold Ambient Weather?

start a car in cold weather

Many of the car users might not be aware of a cold start condition but it is a very critical part to take care of. Cold start is an attempt to start an engine when the ambient weather condition is cold. In extremely cold weather condition, it becomes difficult to start the engine. It can cause a lot of harm to the mechanicals of an engine if the engine is pushed until the temperature of the engine reaches its optimum operating temperature.

We will discuss engine cold start in two parts, routine cold start & extreme cold start.

1) Routine Cold Start of the Engine –

A routine cold start is starting the engine for the first time during the day when the engine temperature gauge indicates the cold state. In this condition, always idle the engine at least for 1 minute after the first start. It is necessary for the engine to develop necessary oil pressure and lubricate the internals. If possible, wait for the engine temperature needle until it starts climbing. Once the needle starts climbing, you can get the car moving. Until the needle indicates the optimum temperature is obtained, do not cross 1500 RPM. Strictly refrain from revving the engine at higher RPM.

2) Extreme Cold Start (Sub-zero temperature) of the Engine

Under the sub-zero temperature circumstances, many factors affect the process of starting an engine. These factors include the temperature of engine oil, fuel and batteries.

1) Cold Engine Oil –

The viscosity of an engine oil changes with the change in temperature. The engine oil becomes thicker with the decrease in temperature and it can not flow easily. It becomes tough for the battery to move the engine parts through it. Thus, it is more difficult to cold start a diesel engine as compared to a petrol engine.

Modern engines use multi-weight oil. Multi-Weight engine oil is designated by “#W##”. The number before ‘W’ indicates the oil’s capacity to flow at low temperature and the number after ‘W’ indicates the oil’s capacity to flow at high temperature. Synthetic engine oils help immensely for varying temperature circumstances.

2) Fuel Freezing –

Freezing of fuel line is another common reason which prevents easy starting of the engine in extremely cold weather. Here is the care/process to follow for your car.

i)  Petrol Engine –

  • Petrol engines do not find more difficulties in extreme cold start condition due to very low freezing point of petrol fuel. However, the presence of water particles in the fuel line may freeze and block the flow of fuel. In such condition, steaming the fuel line would resolve the issue.

ii) Diesel Engine –

Diesel engines have a tough time getting itself stared in extremely cold temperature. Diesel fuel transforms into its solid form(gel) below -8.1 °C. It becomes impossible for the gel form to flow in the fuel line due to gravity.

Diesel engines have a glow plug or block heater because combustion in a diesel engine takes place entirely by the temperature achieved through compression. Following the below tips can significantly help in cold-starting a diesel engine.

  • Pour Anti-Gel in the diesel tank. If the diesel is already in gel form, use De-Gel.
  • Steam the fuel-lines/fuel-filter if clogged due to diesel-gelling. Steaming the engine block may also help the cold-start process.
  • REFRAIN from adding kerosene into the diesel tank. Kerosene does not have better lubrication property and it can harm the fuel-injector badly.
  • Wait for the sun to rise if the engine does not start.
  • At night, cover the engine block and radiator with blankets. Also, try to cover the whole engine bay. This helps the engine in retaining the heat.
  • Cover the whole car perfectly.

Common car-care for the extreme cold condition –

  • Always maintain the correct mixture of coolant and water recommended by the manufacturer.
  • Check the condition of the battery cell. Battery plays the most vital role in the process of starting an engine. The weak battery cell may freeze and break the battery.
  • Windscreen washer may freeze in the washer fluid tank as well as in the pipes. This may lead to failure of motor-pump as well as the breaking of pipes. Ensure that you have added the anti-freeze additive in the windshield washer fluid. If not, empty the fluid.

Considering the above points will significantly help you if you live in an extremely cold condition or visiting one in your next vacation.


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