What is a cold start and why is it important?

If you have started a vehicle that hasn’t been used for a while, you will notice that its engine will idle at a higher RPM (revolutions per minute) than normal. This is what is known as a cold start, it means that the engine isn’t yet at its optimum temperature and therefore is “cold.” While some may worry that something is wrong, a cold start is completely normal and is part of getting your car’s engine up to temperature. This is part of an important process to ensure that everything in your engine is well lubricated so it can function properly.

Getting into the technical side of things, a cold start not only lets your engine get up to temperature, but will also let the oil within get warmed up. Oil is a critical fluid in your motor as it keeps all the moving parts well lubricated and functioning optimally. If an engine hasn’t been used for a long while, let’s say from when you park your car at night to when you start it in the morning, most of the oil settles at the bottom of your engine. While there will still be residual oil at the top of the engine, it isn’t enough protection especially if you run your engine hard from its start-up. This is why it is important to give your engine a few seconds to get that oil pumping and up to temperature.

Getting your oil up to temperature will depend on its viscosity or its ability to be easily poured at a certain temperature. Its viscosity might be thicker at colder temperatures reducing its ability to flow and limiting its capabilities in creating a thin layer of protection for the moving parts. If you let your engine warm-up via its cold start function, this will allow time for your oil to get up to temperature and flow better.

This will depend on your vehicle, however, a typical cold start will hover above 1,000rpm and may even initially exceed the 1,500rpm range. Do not worry, as the engine warms up the RPMs will slowly start to decrease and your motor will return to its normal idle range. Only worry if even after reaching its optimum temperature, the engine still does not go back to its normal idle, this could be a sign that something is broken within the motor itself and will require immediate attention. 

For older model vehicles it is recommended that you warm up your engine first before setting off. This especially applies to vehicles that still run on carburetors. However, if you have a modern engine with tighter tolerances and that uses electronic fuel injection, then you can choose not to warm up your engine. This will allow you to drive the vehicle to where you need to go, but keep in mind that the oil will need time to get up to the correct temperature as well. It is highly advised that you drive slowly and at lower revs so that you don’t strain the engine until it reaches its operating temperature. Once it reaches its operating temperature or the cold temperature light on your vehicle turns off, then you can proceed to drive it normally.