What your Diesel Smoke is telling you

in Blog

It is just a fact that diesel trucks have more smoke than regular trucks. Sometimes there can be excessive smoke though and not every smoke is created equal. Sometimes just by the color of your smoke you can tell what is going on in your engine. Here are some colors that will give you a good idea of what is going on.


Diesel exhaust pipe

This smoke is what you see the most. It often means that there is incomplete combustion of fuel. This means that the fuel is entering the combustion chamber but not being all the way burned by time it exits. This can be caused by anything from timing to a damaged air intake filter. It is pretty obvious that your fuel consumption is not being optimized and you are also losing power.


This sort of smoke actually lets you know that some fuel isn’t burning and that there is large amounts of water vapor in the engine. Sometimes this can also be cause as coolant leaks into the combustion chamber. Sometimes this happens due to a crack in the manifold, improper sealing, faulty injectors, or timing once again.


Blue smoke can indicate that there is oil that is being mixed in with your fuel and that it is being burned. Somehow it is making its way into the combustion chamber. This often means that the oil level is too high or the piston rings are faulty.

It is important to know what is going on with your diesel truck so you can pass your smoke test. It is also important to understand what is going on in your engine and knowing what the smoke actually signifies. You can do many of your own repairs and have a good idea of what remedial action to use in this case.

photo credit: SoulRider.222 via photopin cc

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