* Engine oil leaks: If engine oil leaks onto the exhaust manifold, it can burn and produce smoke.
* Coolant leaks: If coolant leaks onto the exhaust manifold, it can also burn and produce smoke.
* Transmission fluid leaks: If transmission fluid leaks onto the exhaust manifold, it can also burn and produce smoke.
* Worn piston rings: Worn piston rings can allow oil to leak into the combustion chamber, which can then burn and produce smoke.
* Faulty fuel injectors: Faulty fuel injectors can cause the engine to run rich, which can also produce smoke.
If your car is smoking, it is important to have it checked by a qualified mechanic to determine the cause and get the problem fixed.