Exhaust Smoke. What Does It Mean?

What does engine smoke mean? Three types of smokes that can be found on petrol and diesel engine that is white, blue and  black smoke. When smoke come out from exhaust, mean that something wrong with the engine. But there is an exception that when you start the cold engine especially in the morning, you will see white smoke blowing from an exhaust and a little bit drop of water from the exhaust tip and disappear when the engine was warmed up to its operating temperature. That is normal. But if the smoke continuous blowing, better ready with budget on it.

Blue smoke - The engine burning oil. Check the engine oil level on the deepstick, the oil could be getting into the lowest level and this is very dengerous that can damage the whole engine. Go the the nearest service center for compression test. Possibility of cause:

• Worn  piston ring
• Worn valve
• Worn valve seal
• Scratch cylinders

White smoke - The engine burning coolant. Check the coolant level in the radiator and also in the reserve tank. The coolant could be burn together with the air/fuel mixture because because of this;

• Leak/blown head gasket
• Cracked engine head or block

Black smoke - The engine air/fuel mixture is too rich. This is normal for diesel engine when cold start but abnormal for petrol engine. Possibility of cause;

• Broken automatic choke for carburator engine
• Leak/faulty fuel injector for Electronic Fuel Injection (EFI) engine
• Too high/much fuel pressure
• Clogged air filter

Another tips

• If the smoke come out during engine idle and in normal operating temperature, the piston ring worn and need to do general overhaul.
• If the smoke come out only when throttle or speeding, the valve seal need to replace (top overhaul)
• If the smoke come out during idle and speeding, the engine head/block could be cracked.