Menu

Causes of Petrol Engine Blowing White Smoke from Exhaust

December 3, 2016 | Engine Info

If you start up a vehicle with a petrol engine and you notice white smoke blowing out of the exhaust pipe, there are a few reasons why this could be happening. For starters, if it is cold outside then you don’t have anything to worry about because condensation will cause steam to form when you first turn on your engine. But after the engine has a few minutes to warm up, the condensation will scatter and cause the smoke from the exhaust pipe to become invisible like it’s supposed to be.

Dangerous Engine Blowing White Smoke Causes

However, if you continue to see white smoke coming out of the pipe after the engine has had a chance to warm up, then your coolant might be leaking internally. The most noticeable symptom of internal coolant leakage is when the white smoke is billowing out of the exhaust pipe and leaves a sweet odor in the air. If you the white smoke consistently comes out and the sweet odor smell is present, then it is definitely a problem with your coolant leaking.

The reason why coolant usually leaks is because there could be a crack in the engine block or cylinder head. Even if the crack is small, the internal coolant can easily leak out and contaminate the oil of your engine. This is how the exhaust smoke ends up turning white. The combination of the coolant and engine oil will create a milky appearance in the smoke. All it takes is for just a little bit of coolant to get into the combustion chamber for white smoke to be produced. Once you have a low coolant level and a cooling system that isn’t being maintained properly, your engine will start to overheat more easily. This will cause your head gaskets to fail because they won’t be able to seal properly when they’re overheated. As a result, your engine will get worn out much faster and its internal components will get damaged.

Another Dangerous Causes

Another cause are oil leak from valve oil seals or piston rings. In this case, the oil comes into combustion chamber then will burn together with fuel, So it will produce blue or white smokes that comes out from exhaust manifold.

Inspection Tips: Piston Rings or Valve Seals Leaks

To inspect and determine the leakages come from piston rings or valve seals, here are some tips that you can do by your self at home:

  • Remove first EFI fuse
  • Open the spark plugs
  • Fill little oil into the cylinder
  • Put compression test into cylinder
  • Crank the engine
  • See compression, if the result at standard level, you can determine the leakages come from piston rings. But if the compression below the standard, you can determine that leakages come from valve oil seal.

Read also: Common Causes of Car Losing Power When Accelerating

If you want to fix this white smoke problem, the easy solution is to take your vehicle to the nearest auto body shop as soon as you notice it. But if you are trying to fix this yourself, never try to remove the coolant reservoir cap with the car still running because the engine will be too hot and it will cause you serious injury. Once the car has had a chance to cool down, check the reservoir and see what the coolant level is at. If the coolant appears to be at the normal level, then you’ll need to have a cooling system pressure checked performed so you can pinpoint where the coolant leaks are coming from.

Related For Causes of Petrol Engine Blowing White Smoke from Exhaust