How to Repair Exhaust Smoke

exhaust smoking

Anytime you see excessive smoke or steam being produced from the exhaust pipe is means there is a problem. The color of the smoke determines what system could be malfunctioning. A small amount of smoke or steam from the exhaust pipe of the car is normal at start up or under power. Typically, once a vehicle starts producing smoke the pattern will continue until the engine is repaired.

What color is the smoke?

The color of the smoke will help determine what to look for when troubleshooting the problem. Now, when we say the "color" in some cases it will be the tint of the smoke from example blue smoke will be a light gray with a blue hue. Black smoke is basically a very dark gray while white smoke or stream is plain white.

What goes wrong?

Smoke is always caused by a liquid being present inside the combustion chamber that is not normally there such as coolant, excessive fuel or engine oil. Each symptom has its own set of problems and costs to be associated with.

Let's Get Started!

First and foremost we must decide what color smoke or steam it is. This can be best done in a good lighting condition preferably in the daytime. Try to determine when the smoke is best seen ie: engine cold, hot, under power, at idle or at start up only. Most of the time the problem is not a single occurrence and can be repeated. Set up an observer either at the rear of the car or in a chase car behind if the smoke only occurs when driving.

Exhaust smoke or steam will be classified as: white steam smoke/steam (coolant), blue smoke (oil), or black/dark grey smoke (fuel).

Sometime fuel additives can cause colored smoke as well. This condition is normal and will subside when the cleaner has run its course.


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