It’s not unusual for mechanics to deal with cars emitting different types of smoke from the exhaust. However, what many car owners fail to understand is that the severity of the issue depends on the type of smoke.
For instance, white smoke from the exhaust is popular, and it’s not only produced when the car is on the move. Sometimes you find the smoke coming out even when the car is idle or when it’s cold outside.
All in all, no matter how you notice the white smoke, it is essential to take care of the problem before it gets worse. Therefore, take a trip to your mechanic in order to avoid any further damage to your engine or exhaust system.
Although it’s good to leave the job to the professionals, we believe it is also wise to have some general information on what causes the white smoke.
That’s why in today’s article we are going to share with you what white smoke means, its main causes, as well as answer some other questions related to this issue.
What Does White Smoke From Exhaust Mean?
White smoke coming from your vehicle’s exhaust usually indicates something is wrong with the engine or one of its linked components.
Unlike black or blue smoke, which can indicate a variety of faults, white smoke is frequently related to coolant or water entering the combustion chamber. Car exhaust system repair might be needed when you see a car blowing white smoke.
The hue of the smoke can reveal important information about the nature of the problem. White smoke indicates that water vapour or coolant is consumed alongside the fuel in the combustion process.
This is cause for concern because it suggests a possible internal engine problem. Auto car mechanics are essential here, and they can fix this problem for you.
Simply googling “exhaust muffler shop near me” or “exhaust pipe shop near me” can help you find a local car mechanic to examine and repair your car exhaust system.
What Do Exhaust Emissions Normally Look Like?
Before delving into the specific sources of white smoke, it’s important to understand what normal exhaust emissions are. Your car should release practically colorless exhaust gas during a proper combustion process.
This gas is mostly nitrogen, carbon dioxide, water vapor, and traces of other gasses. Exhaust pipe repair and Muffler leak repair are the two most common resolutions to white smoke conundrums.
Variations in the color of exhaust smoke, on the other hand, can indicate a variety of problems:
- Black smoke: This indicates that an excessive amount of fuel is being consumed, which can be related to issues such as a blocked filter, malfunction of fuel injectors, or a fuel pressure regulator malfunction.
- Blue smoke: Indicates that oil is being consumed in the combustion chamber, indicating the presence of potential issues such as worn piston rings, valve seals, or a faulty PCV system.
- White Smoke: As previously said, white smoke from the exhaust is frequently a symptom of coolant or water entering the combustion chamber, which is the topic of our discussion. Car blowing white smoke but not overheating or the white smoke coming out of the exhaust is a clear symptom of this.
If your engine is overheating, but coolant is full, it might be due to cooling system leaks, thermostat issues, radiator problems or water pump failure.
Types of White Smoke
For starters, the car exhaust ensures that harmful gases from your car engines are safely released. They are your “car lungs.” Generally, white smoke being released from the car exhaust can be classified into two:
Thin White Smoke
Suppose you have experienced thin white smoke from your exhaust, especially during cold seasons like winter, that is perfectly normal and not a reason to worry.
Thick White Smoke
Unlike thin white smoke, thick white smoke from the exhaust indicates some function failure that requires immediate repairs or replacement of faulty parts. If you continue to drive the car in that state, you will risk costly and severe damage to your car engine.
Thick white smoke from exhaust might indicate that coolant or water has unintentionally entered the combustion chamber (an enclosed space in the car where air and fuel mixture is burned), which they should never have.
When water or coolant has burned within the engine block (a part of the internal combustion engine), it produces thick white smoke that leaves through the exhaust.
What are the Main Causes of White Smoke from the Exhaust?
White smoke from the exhaust can be caused by several issues:
#1. Blown gasket head.
A blown head gasket can lead to white smoke in the exhaust by allowing coolant to leak into the engine’s combustion chamber.
The head gasket serves as a seal between the engine block and the cylinder head, and when it fails, this seal is compromised, allowing coolant to seep into areas where it shouldn’t be.
Once the gasket is blown, coolant enters the combustion chamber, where the air-fuel mixture ignites to power the engine.
During this combustion process, the engine burns not just the fuel but also the coolant, producing white smoke that exits through the exhaust system.
This issue is serious and needs immediate attention, as continued driving can result in more extensive engine damage.
If you suspect a blown head gasket, we recommend having your vehicle inspected and repaired by a qualified mechanic as soon as possible to ensure your safety and keep your car running smoothly.
#2. Damaged radiator.
A damaged radiator can indirectly cause white smoke in the exhaust by leading to engine overheating, which can damage the head gasket.
The radiator is crucial for cooling your engine, and if it’s damaged, the engine may overheat – putting stress on components like the head gasket.
Overheating can cause:
- The head gasket to fail
- Allow coolant to leak into the combustion chamber
If this happens, the coolant gets burned along with the fuel, producing white smoke that exits through the exhaust.
#3. Cracked engine block.
White smoke happens when coolant leaks into the combustion chamber through a crack in the engine block. It mixes with the air-fuel blend and burns off as white smoke.
Before this happens there are warning signs to watch out for:
- Engine overheating
- Unexplained coolant loss
- Oil contamination
- Reduced engine performance
Address these warning signs as soon as they occur to stop further damage to your engine. To keep your car running smoothly, get it checked by a professional.
#4. Cracked cylinder head.
A cracked cylinder head can lead to white smoke coming from your exhaust, caused by coolant leaking into the combustion chamber. This coolant mixes with the air-fuel mixture and burns, resulting in white smoke exiting through the exhaust.
#5. Condensation.
When you start your car in cold weather, you might see white smoke coming from the exhaust. This happens because moisture from the air collects inside the exhaust system.
As the engine warms up, it turns this moisture into steam, which then comes out as white smoke. Usually, this smoke goes away after a few minutes once the car heats up. It’s a normal and not a sign of any problems with your engine.
#6. Foam in the engine oil.
Foam in the engine oil can cause white smoke from the exhaust. This usually means that coolant has mixed with the oil due to a problem like a blown head gasket or a cracked engine block.
When this happens, coolant can get into the engine’s combustion chamber and burn along with the fuel, creating white smoke that comes out of the exhaust.
#7. Overheating.
If your engine is overheating, it could lead to white smoke coming from the exhaust. When the engine gets too hot, critical components like the head gasket can fail.
A blown head gasket can allow coolant to leak into the engine cylinders, where it’s burned along with fuel.
This produces thick white smoke from the exhaust. Overheating can also damage the engine block or cylinder head, leading to cracks and further leaks of coolant, intensifying the issue.
#8. Low coolant.
Low coolant levels can also be a cause of white smoke from the exhaust. If the coolant level drops significantly, it may indicate a leak or a faulty component like the water pump or radiator.
When coolant leaks into the combustion chamber, it burns off and produces white smoke. Keeping the coolant system properly filled and sealed is essential for preventing this issue and ensuring the engine stays cool.
#9. Air in cooling system.
Air trapped in the cooling system can disrupt the flow of coolant, leading to engine overheating. When coolant cannot circulate properly, it may cause localized overheating and force coolant into places it shouldn’t be, like the combustion chamber.
The result is often white smoke from the exhaust. Air in the system can be introduced due to a coolant leak, improper filling of the coolant, or a malfunctioning radiator cap. Bleeding the air from the system can help restore proper function.
To make sure white smoke from your exhaust doesn’t affect your journey, you can get breakdown cover – simply call us out and we’ll give you Roadside Assistance if your car breaks down.
How to Diagnose the Issue
If you notice white smoke coming from your exhaust, it’s important to diagnose the root cause before any potential engine damage can occur. Here are the steps to follow:
#1. Check Coolant Level.
The first step is to check your vehicle’s coolant levels. Locate the coolant reservoir (aka: overflow tank) under the hood. If the coolant level is below the recommended mark, it could indicate a leak causing the white smoke.
If that’s the case, the problem is serious if the leak is happening in the engine block or cylinder head. But it’s also possible you have a small leak elsewhere which isn’t the cause of the white smoke.
#2. Inspect the Engine for Leaks.
Perform a visual inspection of the engine bay, looking for any signs of coolant leaks. Check hoses for cracks, holes, or loose connections, and inspect the radiator for damage.
Don’t forget to look underneath the vehicle for any pooling of coolant on your driveway or garage floor.
If you discover a leak, try to identify its source and assess the severity. Small leaks may be repairable, while larger ones may require professional assistance.
#3. Check the Oil Condition.
Checking the oil is a simple but important step. Remove the oil dipstick and look at the oil’s consistency and color. If the oil appears milky or has a foam-like texture, it may be contaminated with coolant, suggesting a potential head gasket issue.
In this case, don’t continue driving! If you ignore that warning, there’s a good chance severe engine damage will be the result and you’ll have even bigger problems.
#4. Use an OBD2 Scanner.
If your vehicle has an On-Board Diagnostics (OBD) system (all vehicles since 1986 do), an OBD2 scanner can help identify issues related to the coolant system, fuel injectors, or engine control unit.
Plug the scanner into your vehicle’s OBD2 port (usually located under the dashboard) and follow the device’s instructions to retrieve error codes. You can then research the meaning of the codes or consult a mechanic for interpretation and guidance on what to do next.
#5. Inspect the Fuel Injectors.
If the white smoke isn’t related to coolant, inspect the fuel injectors for any signs of leaks or damage. A faulty fuel injector can cause white smoke by allowing excess fuel to enter the combustion chamber.
To check the injectors, look for any visible cracks or leaks, and ensure the electrical connections are secure.
In most cases, having a professional mechanic perform a more thorough inspection is highly recommended. They’ll be able to quickly identify a bad fuel injector and replace it if necessary.
#6. Perform a Compression Test.
A compression test helps determine if there’s an issue with the cylinder head, piston rings, or valves. This test requires a compression gauge and involves removing the spark plugs and cranking the engine to measure the pressure within each cylinder.
If one or more cylinders show low readings compared to the others, it could indicate a leak. Performing a compression test is not in the skillset of most car owners, so you’ll probably want to seek help from a mechanic.
#7. Consult a Professional Mechanic.
It should go without saying that if you’re unsure about the diagnosis or lack the necessary tools and expertise, consulting a professional mechanic is the best course of action.
They have the knowledge and equipment to accurately diagnose the issue causing the white smoke.
Attempting to fix the problem yourself without the right tools or knowledge could lead to further damage and more costly repairs in the long run.
How Do You Fix White Smoke from Exhaust?
There are various parts of the car you should check to determine why your exhaust gives off white smoke. One of them is the head gasket while the other one is the coolant. There are several steps you need to take to be able to fix the white smoke issue.
#1. Intake Manifold Gasket.
Check Out The Intake Manifold Gasket
The first thing you should check out when you see white smoke coming out of your exhaust should be the intake manifold gasket. As you know, this gasket seals the manifold not only transporting coolant to the engine but also oxygen.
If the intake gasket gets damaged, the engine gets overheats due to the leakage of coolant, air, and gas. Keep in mind that the gasket is mostly made of rubber or plastic.
Therefore it is prone to damage caused by extreme heat. Although it can get cracked or damaged, it can easily be repaired if detected early.
Further, Examine the Head Gasket
After checking the intake gasket, you should move on to the head gasket. This gasket is designed to seal the head to the block.
Its main function is to so prevent the coolant from going where it is not supposed to. If the head gasket has an issue, it needs to be fixed immediately.
Look Closely for Cracks in the Cylinder Head
As you know, the cylinder head is connected to the engine block and head gasket. Due to the fact that it’s made of aluminum, it’s prone to warping or breaking if your car overheats, thus releasing the white smoke.
Therefore, it is necessary to carefully check it and if you spot a crack, change it right away.
#2. Coolant Level.
Inspect the Coolant Level
The first step is to open the hood of your car and inspect the coolant. However, don’t forget that the engine should be cool before you remove the radiator cap or reservoir cap.
If the engine is hot, give it 30 minutes or so to cool down before you attempt to check the coolant.
Open the Coolant Reservoir
After you’re sure the engine has cooled off, open the coolant reservoir and see if the coolant level is the cause of the white smoke.
One way to check the coolant is to look into the coolant chamber or put a stick into its reservoir and check how much coolant there is.
Keep in mind that the stick will give you the exact amount of coolant left in your car, which is more accurate than just looking inside the coolant chamber (what else are you going to look at it with?).
Check Other Areas of the Engine
If the amount of coolant is adequate, it’s time to move to other areas of the engine, such as the cylinder head, head gasket, and even the engine block itself.
Check if these parts have any cracks or damage that may lead to the coolant mixing with the oil or fuel. If it’s possible, you should also perform a cooling system pressure check to try to determine which part is actually causing the leak.
Why is the smoke white in Color?
The smoke appears white in color because it’s made up of water vapor or steam.
When coolant leaks into the engine’s combustion chamber, due to a blown or damaged head gasket, it gets heated and turns into steam.
Unlike the darker color of smoke from burning oil or fuel, steam is light and often appears white as it condenses in cooler air upon exiting the exhaust.
The Difference Between Diesel Engine and Petrol Engine White Smoke from Exhaust
The difference between a petrol and diesel car releasing white smoke is brought about by different problems. That’s why it is essential to know the main causes.
Diesel Engine
When you encounter white smoke in your diesel-powered car, it means the fuel is not burning correctly due to a lack of heat in the combustion chamber.
The un-burnt diesel does not only cause white smoke but also contains certain toxins that will likely sting your eyes.
There are several causes of white smoke in a diesel-powered car. These include:
- Water is mixed with the diesel, which is mostly in the cylinder head or block or is caused by a cracked head gasket.
- Damaged injectors
- Low cylinder compression
- Broken injection timing
- Cracked or damaged rings or cylinder liners
- Damaged fuel lines
- Low fuel pressure to the fuel pump
- Incorrect or broken fuel pump timing
- Broken crankshaft keyway
Most cars experience a coolant leak when a broken head gasket or cracked cylinder head, or damaged engine block is at fault.
Petrol Engine
Just like diesel-powered cars, the petrol engine has various causes that result in white exhaust smoke. Before we look at the causes, it is good to note that white smoke in a petrol engine is caused by water entering the cylinder and mixing with the fuel.
Basically, the white smoke is steam and is kept away from the cylinder by the head gaskets. Inside the cylinder, a mixture of fuel and air mix together, compresses and finally ignites to enable the car’s engine to function properly.
Therefore, any amount of water that enters this area will produce steam that is presented as white smoke in the exhaust pipe of your car.
If white smoke is present, all you have to do is check for the proper amount of water inside the radiator and the overflow tank. Don’t forget also to check if the engine oil is also contaminated.
So, which are the other common causes of white smoke?
- Engine Overheating
- Faulty fuel pump
- Broken injection pump
- Best Automotive Smoke Machine Reviews or valve timing
- The damaged or broken fuel injection system
How to Prevent White Smoke
Preventing white smoke from your vehicle’s exhaust requires proactive maintenance and careful attention. Here are some important steps to take to keep your engine running smoothly and avoid white smoke issues.
Regular Maintenance
Following a periodic maintenance program is critical. Check and change the engine oil, coolant, and other fluids regularly to ensure they are at ideal levels and free of impurities. This reduces the possibility of coolant leaks or dilution with engine oil.
Cooling System Maintenance
Keep the cooling system in good working order by inspecting the hoses, radiator, and water pump for signs of wear or leaks regularly. Because overheating can contribute to white smoke issues, a properly working cooling system is critical.
Fluid Level Monitoring
Closely check fluid levels, especially coolant. Sudden reductions in coolant levels may indicate a leak, which should be addressed as soon as possible to prevent coolant from entering the combustion chamber.
Avoiding Overheating
Avoid engine overheating by correcting faults such as a faulty thermostat, a damaged radiator fan, or clogged cooling channels as soon as possible. Overheating can harm components such as the cylinder head or head gasket, resulting in white smoke.
Gasoline Quality and System Maintenance
Use high-quality gasoline to avoid water contamination. Inspect and change the fuel filter regularly to clear the fuel system of pollutants that could contribute to white smoke.
Cost To Repair Exhaust Smoke
Since most of the repairs required to fix exhaust smoke are difficult, the bill will not be cheap. Since there can be many different causes of white smoke, we will briefly discuss the average repair costs of each problem.
This will give you an idea of how much it will cost to repair your car based on the specific problem.
- Blown Head Gasket – A blown head gasket is not the worst thing that could happen, although the cost to repair a head gasket will not be cheap. It will take a mechanic several hours to complete the job, and the average cost of repair is about $1,500 in most cases, even though the head gasket kit might cost less than $100. If you have a high-end vehicle, the cost could exceed $2,000 for parts and labor.
- Cracked Engine Block – A cracked engine block is likely the worst-case scenario. If the crack is small, a mechanic might be able to repair the crack. Even repairing the crack is likely to cost you $2,000 on average. Unfortunately, not all cracks can be repaired. In that case, you’ll need to replace the engine block. Expect to pay around $3,000 to $5,000 for a new engine block.
- Bad Fuel Injector – Replacing a bad fuel injector won’t usually break the bank. In most cases, a repair shop will replace a fuel injector for about $200 to $300.
- Condensation Burnoff – There is no cost associated with this repair because no repair is needed! Simply drive your car, and the smoke will go away.
- Oil In The Combustion Chamber – Oil in the combustion chamber is usually the result of bad piston rings or bad valve seals. Either of those repairs is not cheap, and you can expect to pay around $2,000 to replace the rings in most cases. Replacing valve seals might be slightly cheaper, but ring replacement can even approach $5,000, depending on the make and model of your car.
- Bad Intake Manifold Gasket – Replacing an intake manifold gasket is not a terribly expensive repair. On average, you can expect to pay about $250 to $450 for it. The gasket itself might only cost you $20 to $50, but it will require a couple of hours of labor.
- Cracked Cylinder Head – Replacing a cracked cylinder head will be an expensive repair because the part is expensive, and the job requires several hours of labor. Usually, you can expect to pay around $2,000 to have a cylinder head replaced, although the job can cost several thousand more dollars if you have a high-end vehicle.
If you have white smoke from your exhaust, one of the items above is more than likely causing it. Now you have a better idea of how much it will cost to fix these problems!
FAQs.
Q: Can I Drive My Car with White Smoke?
It’s really not a good idea to drive your car while there is white smoke coming out of the exhaust. Why is that you ask?
First of all, it means your car may have engine problems such as an engine oil leak that may drip from the car’s gasket.
This might cause serious damage to the car’s engine or even start a fire. Therefore, ensure you get your car checked out immediately if you notice any white smoke coming out of the exhaust.
Q: What Causes White Smoke From Exhaust When Accelerating?
Simply put, there are two ways that cause white smoke from the exhaust when accelerating. One of them is because of the transmission fluid and the other is burning coolant.
When we look at the transmission fluid issue, white smoke is present when the engine sucks fluid through its vacuum hoses.
Additionally, the smoke is also known to leave behind an oily smell. Aside from that, a vehicle burns coolant when the car’s cylinder head or gasket is cracked and starts leaking.
This usually is bad news as the leak gets mixed with the engine oil therefore it contaminates it which results in white smoke. Keep in mind that the white smoke will also have a lightly sweet smell to it.
Q: What Causes White Smoke From Exhaust When Idle?
The most common factor we know of that leads to white smoke when the car is idling, is oil getting inside the combustion chamber (not necessary, it is implied).
This simply means that the presence of oil in the combustion chamber goes into your car’s exhaust system and creates white smoke.
It is quite easy to know the presence of oil as it’s different from gasoline in terms of color and smell. But hey, don’t forget that this problem should be dealt with as quickly as possible to avoid any further damage, such as the spark plug.
Q: What Causes White Smoke From Exhaust to Smell Like Gas?
Mostly what causes white smoke from exhaust smells like gas is water vapor. This happens when the water finds itself in the combustion chamber. When this happens, you see water dripping from the exhaust pipes.
If you do find water in the fuel, you should replace the fuel immediately before driving the car (implied). Although most owners think it is normal, you should take your car to the mechanic and have it fixed immediately.
Q: What Causes White Smoke from Exhaust When it is Cold?
It’s quite common to see white smoke from the exhaust when cold. You should be concerned if you notice continuous smoke while driving, especially if you are having a diesel car.
That’s because the smoke may be present due to leakage of coolant going through the engine. It could also vet be from incorrect fuel injector timing.
Ideally, it is good to pay more attention to the white smoke your car releases when it’s cold outside in order to avoid any further damage.
Q: How Much White Smoke from Exhaust is Normal?
One factor that should not worry you is when you see the thin white smoke from the exhaust. That’s because the smoke is probably a result of steam that forms in the exhaust system. Since the white smoke is most likely vapor, it usually disappears quickly.
This kind of thin smoke is seen mostly when it’s cold outside or when you first start the car. However, if you notice the smoke getting thicker and doesn’t go away, we recommend you visit your mechanic.
Conclusion
I don’t think there is anything else we can add concerning white smoke. As you have learned, just like the black smoke, as well as other types of smoke coming out of your exhaust, white smoke is not something to be ignored.
Not only does the smoke cause problems (implied), but it can also affect other cars that are driving behind you.
It’s very crucial for you to notice early on if there is white smoke coming out of your car’s tailpipes.
Meanwhile, if you find any trace of smoke, you should make sure it is not just steam or caused by the outside temperature. So, tell us to have you noticed any white smoke coming out of your exhaust lately.