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Main causes of white smoke from the car’s exhaust

White smoke that is released on the exhaust pipe is a sign that there is a problem with your car.

The severity of the problem may vary depending on the type of smoke. This problem could have many causes. So, in this article, we will try to get you an idea of the root causes of the white smoke problem and what is the best way to eradicate this disturbing problem.

What does white smoke from your car mean?

White smoke can be an insignificant problem or it can be quite serious and we can see the gravity of the situation by identifying the thickness of the smoke. White smoke is the result of condensation that accumulates inside the exhaust system. So, if it is thin in the form of vapors, you should not worry, because the smoke will disappear quickly. At the opposite end, if the smoke is thicker, then the problem is quite large.

Thick smoke, in general, comes from problems with the engine cooling system, which could lead to many more serious problems, such as damaged cylinder head gasket, engine block breaking, repairs that will not be cheap at all. In this situation, it is advisable not to overlook the problem and urgently go to the mechanic. Coolant leaks, even small ones, can damage the car.

What is your car trying to say to you through the white smoke on the exhaust?

Injection pump and injector defects

If your car is equipped with a diesel engine and produces a lot of white smoke when the engine starts, it means that the injection pump and injectors should be checked. Checking them or modifying them on their own is not recommended, as this task requires a lot of skills that the drivers do not have, so it would be preferable not to try. Plus, your car should be checked as quickly as possible by a mechanic. The fact that your car eliminates a lot of white smoke on the exhaust pipe can be a sign of even more serious problems.

This can mean a malfunction of the fuel pump or, as I said above, problems with the cylinders, the gaskets or even a crack in the engine block. Solving such failures is expensive and it is preferable to deal with the problem as soon as possible.

Coolant leakage

The leaking coolant may be a reason why the exhaust smoke is white. The appearance of this type of white smoke on the exhaust pipe occurs when water or antifreeze enters the cylinders due to overheating of the engine and subsequent failure of the gaskets, and the engine tries to burn them with fuel. Or, if the car does not have coolant, it can heat up and could evacuate the smoke which will, of course, be white. For this reason, the temperature of the car is also very important.

Third-party issues

Often, you can see a white smoke evacuation as the car goes, which could be an indicator of serious problems, the repairs of which will be quite costly. When one of the engine cylinders, cylinder head gasket or fuel filter is damaged or the engine is clogged or cracked, white smoke will be evacuated in large quantities, and replacing these parts can be very costly. The problem in such situations is that you cannot postpone the repair and cannot find a temporary solution. Over time, they worsen and the cost of repairs goes up immediately. Maintaining your car will help you identify such a problem in its initial form and thus help you save some money.

How can you fix the problem of white smoke being evacuated?

To solve the white smoke problem, besides the fact that you can go to the service, if you have mechanical knowledge and have previously performed car repairs, you can do this at home:

1: Check the intake manifold

The inlet gasket is the first component that you must check if there is white smoke coming out of the exhaust pipe. Inside the vehicle, there is a gasket that seals the cylinder inlet manifold. These components have the role of distributing the combustion mixture together with the coolant to the inlet port.

These ports will be placed at the ends of the cylinders. In conclusion, if it deteriorates, the coolant will enter the combustion chamber, creating white smoke while driving. As a result, drivers must remove the intake manifold and examine the intake manifold. If there are leaks or rust, you know where the problem is.

2: Examine the cylinder head gasket

The cylinder head gasket also needs special attention. Don’t forget to take this step only if the inlet gasket works. This is the part of the vehicle that seals the cylinder head to prevent the coolant from reaching it. Any leakage or deterioration in this part facilitates the penetration of the coolant. In short, white smoke will appear on the exhaust pipe. If this component of the car is OK, then proceed to check the cylinder.

3: Look for any cracks in the cylinder head

Don’t forget to check the cylinder head too. The cylinder head is that part of the car that is prone to breakage in overheating conditions. This component is essential because it connects to the engine block and cylinder head gasket. If this component is broken or damaged in any way, you must change it.

Frequently asked questions about car white smoke 

Why does my car has white smoke on the exhaust when it starts?

White smoke can be caused for several reasons. But if white smoke comes out when you start the engine, it could be for these reasons:

  • A cracked or deformed cylinder head;

  • An error of cylinder head gasket;

  • The cracked engine block.

One of the most common causes, the cracked engine block can allow the coolant to leak inside the combustion chamber of the engine and cylinders, which is very dangerous and requires special attention.

What causes white smoke to exhale when accelerating?

The answer is either the transmission fluid or the burned coolant. In the case of transmission oil, the engine inhales the fluid through a vacuum hose, which leads to the white color of the smoke The evacuation will also have a smell of burnt oil. If the white smoke is from the coolant, your car has a crack in the cylinder head or a problem with the cylinder head gasket. In this situation, you can undergo the pressure test the cooling system to see if the cooling fluid is low or the engine has been overheated. If it is low, you can add the required amount of liquid to restore the level.

If there are none of these reasons, your vehicle will most likely leak to the gasket. So you have to replace it to function again in normal parameters.

Why does white smoke from the exhaust smell like gasoline?

Drivers need to understand the concept of car smoke. Usually, it is steam. For this reason, you will have water dripping from the exhaust pipe. Drivers can also see fuel water or a leak in the cylinder head gasket. You might think it’s normal, but this is how the engine fails and pushes the raw fuel out. In these cases, the car will run harder and the drivers will smell raw fuel. To fix this problem, check the fuel and replace it if necessary.

What causes white smoke to escape when the car is stationary?

If the car releases white smoke when idling or stopped, then there may be oil leaks inside. This is very easy to recognize, as there is a difference between igniting the gas/air mixture and the gas/air/ oil mixture. This problem should be solved as soon as possible because the longer the oil stays inside, the more damage it will cause to the spark plugs and injectors, which will need to be replaced.

Why is white smoke coming out from exhaust when it’s cold?

In the cold season, white smoke may be quite normal, but there are exceptions. Continuous white smoke is one of them. If you have a diesel engine, white smoke can be an unburned fuel or coolant that runs through the engine. But in most cases, it’s about the response time of the injectors and the control of the amount of fuel injected.

Conclusion

White smoke from the exhaust pipe is something that drivers should not ignore. Therefore, you should not overlook such a problem because it leads to severe complications not only for you as a driver but also for the other drivers if you do not remedy this before you get back on the wheel. For this reason, it is advisable to always take care of the car you own.