Black Smoke Coming From Your Exhaust?

Why is your car is spewing black smoke from the exhaust and what is there that you can do to correct it?

If your car is running as it should, you will see a thin layer of water vapor coming from the exhaust. On the other hand, if you are seeing black smoke coming from the exhaust, you’ve got a problem. Don’t panic!

We will go over the reasons why black smoke is coming from your exhaust whether you have a petrol or diesel vehicle. We will also give you some tips for repairing the problem.

Reasons Why Black Smoke Is Coming From The Exhaust?

If you are experiencing black smoke coming from the exhaust, the engine is burning an excessive amount of fuel. The fuel could be mixed with too much oil inside the engine or it could be contaminated. This condition happens in both diesel and petrol.

In some cases, the black smoke is signaling a minor problem that can be quickly corrected. In other cases, it could be a serious problem leading to an engine replacement. Either way, check with your mechanic and check out the car’s manual.

Some Reasons For Black Smoke Coming From The Exhaust

A Clogged Air Filter –

Clogged Air Filter

Dust and debris can get into the air filter not allowing enough air to hit the cylinder. This will cause more fuel to be burned which will lead to black smoke.

You might notice heavier smoke when you are accelerating or towing heavy loads.

A Malfunctioning Fuel Injector –

When the fuel injectors work properly, fuel is vaporized and spread into the cylinder. If the injectors are not working properly, the injectors might not close properly or they will become clogged. Either way, this could cause problems.

If added fuel is injected into the cylinders, it will cause the engine to run rich. In other words, there is not enough air in the combustion chamber causing black smoke to come from the exhaust.

A Damaged EGR Valve

An EGR valve recirculates the exhaust gas to reduce emissions of dangerous substances. It will take the exhaust gas and put some of it back into the combustion chamber.

If the valve is damaged on a diesel engine, there are not enough gases being circulated so black smoke will appear from the exhaust.

A Dysfunctional MAF Sensor

MAF stands for Mass Airflow. These sensors determine how much air is getting into the engine. The data will tell the injectors how much fuel to combine for combustion.

On the other hand, if the sensors stop working the wrong data could be sent, causing the engine to think it needs more fuel than it really does. This will create a rich-running climate. When the MAF sensor is dysfunctional, you will also experience performance issues.

Damaged Glow Plugs

If you have a diesel engine, the glow plugs can go bad. You will see other symptoms as well such as having trouble starting your car.

Use a 12-volt test light to check the glow plugs. In some models, it’s very easy to replace them while in other models it can be more difficult.

Engine Deposits

Car Engine Deposits

As the engine gets older, deposits will start to form causing black smoke to come from the exhaust. Deposits of combustion start to build up in the injectors and combustion chamber.

Not only will these deposits interfere with your engine’s performance, but can cause the motor to fail completely. In order to prevent these deposits, it’s important to use the right kind of fuel and get it from a high-end station.

How To Correct Black Smoke Coming From the Exhaust

A Clean Air Filter –

In order for combustion to work properly, there must be a good level of air entering the engine. A lack of air will cause fuel to partially burn which will lead to black smoke.

You should regularly check the air filter to ensure it’s not clogged. The filter should be changed out regularly as well. Replacing the air filter is not expensive and it’s easy to change out without using special tools.

Use Fuel Additives –

Debris and deposits from combustion can build up in the cylinders and fuel injectors. When the deposits build up, savings on fuel will be reduced, performance will be less and black smoke will develop.

There are additives with detergents that will clean out the deposits. Simply follow the directions on the bottle. Normally, you put the additives into the fuel tank after filling up.

Change Sensors –

If the MAF sensor is sending the wrong information, there will be too much fuel in the combustion chamber. You will find the sensor inside the filter housing. You might be able to just clean the sensor and reinstall it but in other cases, you should replace it to get the proper readings.

You Should Replace The Glow Plugs In Your Diesel

If you have not changed the glow plugs in a while, this might be a good time to do so. Like spark plugs in a petrol engine, the glow plugs should be changed during regular maintenance. You can find out when they should be changed in your car’s manual.

Should You Drive Your Car With Black Smoke Coming From the Exhaust?

Car Exhaust Smoking

While this is possible, you probably shouldn’t. When the engine runs too rich, too much fuel is being mixed in the combustion chamber. In turn, this can lead to performance issues. If that happens, you could be left stranded on the side of the road.

Also, excessive fuel that is not burned coming from the exhaust can cause damage to the catalytic converts over time. Keep in mind, that it will be pretty expensive to replace the catalytic converter. Correcting the problem in advance will save you a lot of money.

Keeping up on required maintenance will keep your car running much longer than not doing anything at all. You have invested in your car so do everything you can to keep it in great condition.

If you are having issues with black smoke coming froom your exhaust you can get your vehicle checked by booking online today.

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