The Color Of Your Car’s Exhaust Smoke

By Lawrence Reaves

Exhaust smoke is not a normal occurrence. It implies something is wrong with your engine. The challenge is to diagnose the root cause, so it can be properly addressed. If the underlying problem is neglected, it can worsen to the point that your engine becomes severely damaged.

Smoke coming from the tailpipe displays in one of three colors: blue, white, or black. Each color suggests a different set of problems, and thus plays a key role in the troubleshooting process. In the space below, we’ll describe the most common factors that can contribute to each color smoke.

What Does Blue Smoke Mean?

If you notice blue smoke coming from your tailpipe, it means that motor oil is leaking into one or more combustion chambers. The oil is being burned along with air and fuel when the cylinder’s spark plug ignites the mixture. Even a tiny amount can produce blue smoke. Over time, the spark plug may become fouled due to the burned oil, causing your engine to misfire.

There are several places that can allow oil to gain access to the combustion chambers. Each represents a possible leak. They include the various seals, gaskets, and valve guides as well as the piston rings. Unless you have substantial experience working on cars, finding and replacing the compromised part is best left to a trained mechanic.

What Does White Smoke Mean?

White smoke should not be confused with the thin wisps of steam that comes from the tailpipe when you start your car. Steam is the result of a blast of hot air passing by residual condensation within the exhaust system. It should disappear after a few minutes.

If you see white smoke, it means that coolant is leaking into one or more combustion chambers. Like the oil described earlier, it is being burned with the air-fuel mixture.

There are two main ways coolant can leak into the cylinders. The first way is through the head gasket. Sandwiched between the engine block and cylinder head, it is responsible for providing a seal that maintains compression in the cylinders, and prevents coolant from leaking. A head gasket failure results in a leak, which in turn produces white smoke.

The second way coolant can enter the combustion chambers is through a cracked cylinder head. This problem is less common than a blown head gasket, though just as serious. When cracks occur, they are usually due to overheating, which causes thermal stress in the metal. Cracks may also occur as the result of poorly installed components.

What Does Black Smoke Mean?

Black smoke is caused by excess fuel in the engine’s cylinders. The air-fuel mixture is too rich, and as a result, some of the fuel in the chambers is not burned completely. Of the three types of smoke you may see coming from your car’s tailpipe, this type should cause the least amount of concern. Your engine might suffer slight performance issues, and you may notice a drop in gas mileage. But the underlying cause of the black smoke is unlikely to lead to serious engine damage.

Several factors can cause excess fuel to end up in the combustion chambers. For example, one or more fuel injectors may have developed a leak. Or, if your vehicle is equipped with a carburetor, the choke may have become stuck in a closed position. The fuel pump may be failing. Or, your car’s powertrain control module (the computer) may be receiving bad data from an oxygen sensor. Troubleshooting the problem will likely require the help of a mechanic.

Regardless of the type of exhaust you see coming from your tailpipe, it is important to have the issue resolved. Black smoke is not as serious as blue and white smoke, but should be addressed to maintain your engine’s performance. Realize upfront that repairs for the latter two types of exhaust are likely to be the most costly.

About the Author:

Kansas City GMC

from

Fangman Kansas City Car Dealers

Source:

isnare.com

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