You can get a pretty good idea of what’s going on inside your vehicle when you examine its exhaust system.
If you know what to look for, you can find early warning signs that could end up saving you a lot of money in repair costs. For example, did you know your vehicle’s exhaust smoke color is a good indicator of a problem? We’ll go over what the different colors of exhaust smoke mean so that you can catch issues before they get too severe.
Light White
What you want to see from your exhaust pipe—and an indication that you probably don’t have an issue with your exhaust system—is smoke that’s thin and just a little bit white in color. For the most part, this is usually just vapor exuded once the vehicle heats up and expels collected condensation from its inner workings. This kind of smoke isn’t something to worry over.
Thick White or Gray
If you notice a heavier amount of nonstop white or gray smoke, you have a bigger problem. This kind of exhaust tends to indicate your vehicle’s head gasket has a leak you need to deal with. This leak causes coolant to heat up and get blown out of the exhaust system, causing the continuous stream of white smoke.
Black
Thick, black smoke coming from an exhaust system may not be incredibly uncommon, but it shouldn’t happen to your vehicle if you want it to keep running for a while. Usually, you can attribute black smoke to your engine burning more fuel than necessary. Clogged air filters, fuel injection issues, intake manifold blockages—all of these things can cause your engine to burn more fuel than it needs to. Make sure to get these things checked out soon so that your vehicle doesn’t consistently spit smog out at the cars behind you.
Bluish Gray
Of all the different colors of exhaust smoke, fumes with a bluish-gray tint to them can seem the oddest and most alarming. This kind of exhaust smoke occurs when your engine burns oil instead of gas. Oil leaks aren’t uncommon, as damaged seals and older cylinder walls can cause them to happen, but it’s extremely unhealthy for your vehicle to continue doing this. Tell your mechanic about the blue-tinted smoke so that they know what to look for as they work.
