* Burning oil: This is a common cause. Blue or white smoke usually indicates this. It could be due to worn piston rings, valve seals, or a blown head gasket.
* Burning coolant: White smoke, often accompanied by a sweet smell, suggests coolant is leaking into the combustion chamber. Again, a blown head gasket is a likely culprit, but also a cracked cylinder head or block.
* Fuel system issues: Black smoke usually points to a rich fuel mixture – too much fuel being injected relative to the air. This could be caused by a faulty fuel injector, mass air flow sensor, or other problems with the fuel delivery system.
* Transmission fluid leak: If the smoke smells burnt and is accompanied by fluid leaks, a transmission fluid leak is possible.
* Overheating: Excessive heat can cause various components to overheat and fail, ultimately leading to smoke.
To determine the exact cause, a mechanic needs to inspect the engine. They'll check for leaks, compression, and perform other diagnostic tests.
