Why Is There Smoke Coming From Underneath My Car’s Hood?

You might notice a small amount of smoke escaping from your tailpipe as you start up your car one morning and start to worry. There's no need. This kind of smoke is normal. It's just water vapor from condensation that has gathered in the exhaust system overnight. But a cloud of smoke billowing from underneath your car's hood as you drive? That's the kind of smoke with cause for concern.

Different colors and smells of smoke can help indicate the cause, though it's best to err on the side of caution and take your vehicle to a mechanic if you're concerned.

What Do the Different Colors of Smoke Mean?

White Smoke: This is usually a signal that coolant is being sprayed onto a hot engine by a blown radiator hose. It's usually accompanied by a strong, sweet smell from the coolant.

Black Smoke (with a burning plastic smell): A burning plastic smell accompanying black smoke usually indicates an electrical failure. The smell comes from wires that have burned in a short circuit. As well as the smoke lights and other electrical devices in your car may flicker or fail.

Black Smoke (with a gasoline smell): If you see black smoke coming from your car and you can smell gasoline, it means your engine is burning raw fuel. This can be because of a number of faults, including a leaking fuel injector, defective fuel pressure regulator, or a failed engine sensor. If it isn't repaired, it can cause expensive damage to the O2 sensor and catalytic converter.

What Should I Do If My Car Starts Smoking?

If you see smoke coming from underneath your hood while driving, you should pull over as soon as it's safe to do so. Turn off the engine and lift up the hood so you can see what might be wrong and decide if it's safe to drive to a repair shop or if it's safer to call a tow truck.

If you need engine repair, we invite you to bring your vehicle into our auto repair shop today!