Smoke pouring from a car is concerning. It’s normal for a car with an internal combustion engine to have a little smoke emerging from the exhaust, but a continuous stream can be worrying. Be it your car, or from the car in front, you’ll want to know the situation. Luckily, National Tyres and Autocare have provided some expert knowledge on what different exhaust smoke colours could mean.


Some smoke

Some smoke is to be expected for internal combustion engines, but more consistent or thick smoke can be a sign of something off with a vehicle.

Thin white smoke

This is a normal type of smoke to expect. When first starting your engine, especially on a cold morning, you may see a thin white layer of water vapour. This is a result of condensation build-up within the exhaust as the car begins to warm up. This thin layer of water vapour should eventually disappear.

White smoke

Continuous thicker white smoke should cause more reason to be alarmed. This form of smoke is most likely the result of your car’s coolant leaking into the exhaust. This could be caused by a faulty head gasket or a cracked cylinder head or engine block.

Black smoke

Black smoke is one to be concerned about though. This could mean that your car is burning too much fuel. This problem only applies to diesel and petrol vehicles and there are multiple reasons why this may be taking place. It could be due to a malfunctioning fuel injection system, a blocked manifold or damaged piston rings.

Blue smoke

Blue smoke is another indicator that there is a mechanical problem with your car.  A burning smell often accompanied by blue smoke coming from the exhaust indicates that engine oil is burning. Engine oil is responsible for lubricating vital moving parts of your engine, ensuring that they do not get damaged or overheat. Some reasons for engine oil burning could be worn cylinder walls, leaking value seals or damaged piston rings. After getting a service you may notice this smoke. If it goes after a short while, it is excess oil burning off and is no cause for concern.

What to do if there is a continuous stream of smoke coming from your car?

If you notice that your car is expelling any of the smoke described above it is essential that you get your vehicle seen by a professional straight away. Even if your car is in working order, it is recommended that you visit a garage as prolonged use of the car will be possibly putting yourself and other drivers at risk.