White smoke coming out of Chevy Colorado's tail pipe.

White, blue or black smoke from your car

In Diagnostics by Steves Auto Repair and Tire

It can be a little concerning when you notice smoke from your car exhaust. This occurred to me recently when a friend started their Chevy Colorado. 

If this happens to you, you might think, “What’s wrong?” and “Is it safe to drive my vehicle?”

Before taking off down the road, you need to make sure your car is drivable. There are a few areas you can check:

  • Take a look at the temperature gauge, which tells you if the engine coolant temperature is where it should be.
  • Make sure there aren’t any warning lights or alerts on your dashboard.
  • Check the oil level and coolant level to ensure they aren’t low.

What to do if you notice smoke from your car

Wondering what to do if there’s white smoke from exhaust? What if you notice blue, gray or black smoke from your car? 

Having the car checked out by a trained automotive expert – like an ASE certified technician – is your best and safest option.

If you don’t see any warning lights and everything seems to be OK, drive the vehicle to a nearby auto repair shop as soon as possible.

If there is a problem, or something changes when you start traveling – if it starts overheating, for example – you should pull over at a safe location and call a tow truck. 

Choosing to ignore alerts, low fluid levels, or odd behaviors for too long could lead to more damage.

What do different smoke colors mean?

You can get a better idea of what’s causing the smoke by looking at different factors, like the color and the smell.

White smoke coming out of exhaust can be the result of a few different problems. It may indicate an engine problem or that coolant is going into the combustion chamber. A cracked cylinder head, a head gasket that’s leaking, or a cracked engine block are other possibilities.

A sweet smell is typically associated with antifreeze or coolant. Meanwhile, the smell of fuel can mean that the issue lies with the fuel system.

Blue, gray and black are other colors of smoke to watch out for. If the smoke from your car is gray or blue and you notice a smell that seems bitter, it might mean that the engine is burning oil. The situation could occur if valve seals are leaking, piston rings have become worn, a PCV valve is clogged, or the crankcase is overfilled with oil

Not using the correct kind of oil and not having regular oil changes performed may also cause this problem. We recommend oil changes every 3,000 to 5,000 miles, depending on the vehicle. 

Grey or white smoke coming out the back of the vehicle – but not necessarily the tailpipe – could be an external leak, such as engine oil dripping or transmission fluid leaking from a cooler line onto the exhaust.

Too much raw fuel burning could lead to black smoke that has a gasoline smell, a problem sometimes caused by a fuel pressure regulator that has failed, a bad engine sensor or ignition part, or a fuel injector that’s leaking. 

You should have your vehicle serviced at a car repair shop, because some of them – including Steve’s Auto Repair & Tire, an auto repair shop in Woodbridge, Virginia – perform visual inspections and note anything out of the ordinary, such as oil leaks and coolant leaks. Internal leaks are more difficult to diagnose, but your mechanic can help determine the problem and help you and your family stay safe on the road.

Steve’s Auto Repair & Tire is an authorized Goodyear tire dealer located in Woodbridge, Virginia. Automotive repair services are performed on all makes and models, including BMW and Mercedes. Services include oil changes, brakes, alignments, inspections, and computer engine diagnostics.