Exhaust smoke colour - what is the meaning behind it?

A car is a valuable commodity, not only as a means of transport, but also as an accessory. If something goes wrong, you'll want to know about it as soon as possible. In this article, will take a look at the different types of exhaust smoke colour and the meaning behind them all.

It may look pretty, but...

You don't have to understand the mechanics behind exhaust systems to know when there is a problem. If your car is chugging out coloured smoke, it almost always means that there is a problem and left unchecked, it could develop into an expensive nuisance.

There are four main colours to look for when it comes to exhaust smoke; black, grey, white and blue. If you notice any of these coming from your tailpipe, you might want to consider giving your car some extra attention. Let's take a closer look at each exhaust smoke colour and discover the meaning behind each one.


Black smoke usually indicates there is a problem with the fuel, often signalling that there is too much petrol and not enough air in the combustion chamber. To fix this problem, you could try cleaning your fuel injector, or replacing your air filter.


White smoke could possibly indicate that you have a problem with your cylinder heads or your engine block. Be aware that white smoke can sometimes appear on a cold day, although it usually disappears again once the vehicle has been warmed up.


Blue or grey smoke usually signal similars problem, related to the oil inside the combustion chamber of your car. This could be related to piston rings or valve seals and unfortunately, this is usually not a problem you can fix yourself.

Better safe than sorry

Although our beloved vehicles undergo strict safety checks before they end up in our possession, things can and do go wrong. The slightest error could result in further damage to you or your machine, so if you spot unusual exhaust smoke, regardless of the colour meaning, you should have it checked out as soon as possible.

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