White Smoke From Exhaust: Main Causes and How to Fix

The tailpipe is where the smoke and steam released from the vehicle escape, and usually, it is colorless or may have some dark particles. When you see white smoke coming out from the fume pipes, it could indicate some problem with the engine, and you must fix it soon.

It may damage the car’s internal parts and lead to more expenses if left unrepaired. You must also know that the smoke particles are also bad for our environment and carcinogenic. 

Understand the reason for white smoke 

Emissions from the exhaust pipes can be gray or bluish-white due to the burning mechanism of the engine and the type of fuel used in it. White smoke could be dense water vapor and may disappear soon. But if the smoke is dense and thick, there are many reasons to check for an address. 

1. Condensation may look like white smoke 

During winter months and colder countries, condensation is a common phenomenon. Especially in the mornings, the overnight condensation changes into water vapor and comes out as white smoke. This disperses immediately and stops in a few minutes, and then there is no smoke from the exhaust pipes.   

2. Cracks in the Engine Block 

This is the most serious problem that a car can have when emitting white smoke. When the engine block has a crack, you can only repair it by spending hundreds of dollars at a repair shop. Hence you must explore the other reasons and rule them out before taking it to the mechanics for the engine block repair. 

3. Coolant Leak

If you see white smoke coming out whether the car is idling or accelerating, then the coolant may be the culprit. You can easily detect the leak from the coolant container. You can try to check the smell of the smoke from a safe distance while using a shield to protect the face. In case the smell from the engine is sweet then it’s a sign to understand that there is a problem with the coolant and it might be leaking.

Internal coolant can leak into the combustion chamber in the engine and evaporate with the heat into a cloud of white smoke. Even if the smell is not very sweet or you cannot detect it, it may still cause concern.

In this case, it is better to first have a look at the coolant. But if you suspect that it is leaking then you must take the car to the mechanic as soon as possible. If you ignore it at this stage, the coolant may also leak into other parts of the engine, and the engine oil may also be spoiled, and then it will be a bigger issue to tackle.

In case of an emergency, if you cannot find a mechanic, then stop the car and wait for the engine to cool down before opening the hood to check the coolant level. The mechanics usually use the cooling pressure check to detect the exact place of leakage as they can detect easily due to their experience. 

4. Oil Leakage

Engine oil is a viscous liquid and is very thick. If it enters the combustion chamber, it may lead to white smoke with or without some bluish color. This reduces the efficiency of components in the engine that need this lubricant and may also lead to other problems by covering them in soot. A mechanic can easily identify and repair the leakage. 

5. The Engine Control Unit may also lead to white smoke.

The fuel is injected into the right chamber under controlled conditions using a fuel regulator. The engine control unit may malfunction, and the fuel regulator or injector may not calibrate the fuel correctly.

A mechanic can repair the mechanism by resetting the readings and correcting time calibration. You can try to disconnect the battery and switch off the ignition for some time to reset the fuel ignition timing before going to a mechanic.

6. Fuel Pressure Regulator

The engine needs constant amounts of fuel and air mixture to work smoothly. A faulty pressure regulator may create an imbalance, and the engine may receive too much or too little fuel to burn. The excess fuel will flood the engine, while too little fuel will leave the engine misfiring. Either of these situations may lead to white smoke from the exhaust pipes. 

Diesel engines may see white smoke when the fuel injector pipe and fuel injection timing are not functional. All these problems need fixing by professional mechanics. 

7. Other Reasons

Sometimes the smoke may result from more than one of these reasons. A mechanic or professional can fix it after checking and eliminating it one by one. The repair may cost you some money, but saving the car will be worth it. Unless you are sure of the cause and know the nitty-gritty, do not repair it yourself and seek professional help.  

What can you do?

Once you notice white smoke coming out of the car, you can conduct certain checks yourself. Wait for the white smoke to disperse in a few minutes to confirm if it is condensation.

Check the coolant levels to ascertain whether it is a coolant leakage. There is an intake gasket that seals the intake manifold and you must inspect that. It prevents mixing the fuel-air mixture with the coolant, and a faulty one may lead to white smoke.


Smoke from the exhaust is a normal phenomenon as long as it is thin and colorless. If the smoke is dense and white or bluish tinge, it is alarming for you to check the engine, different components, and the fuel injector and coolant levels. The problem must be rectified before the coolant or fuel floods the engine and damages more sensitive parts.

The biggest point is usually we can see the smoke from other cars, but someone else must point it out to us when it is coming from the exhaust of our cars. Do not wait until you know the car’s status and check the reasons. Try to address the reason as soon as possible or take it to the mechanic when you can. 

Liam Dare

As CEO of ReplicarClub.com, my passion for the automotive world motivates me to build online businesses that provide information and entertainment to users. I am proud to contribute in a positive way to the automotive community.