Well white smoke usually means your burning off coolant. It can be caused by a torn head gasket or intake gasket and also by a cracked head or a cracked intake. But if it doesn't smell sweet, and you don't have compression problems, it probably isn't coolant. Supposedly oil can also cause white exhaust smoke and one way is if the oil is overfilled.
Here were some other comments...
What_can_cause_white_smoke_from_the_exhaust
Maybe a blown head gasket
Telltale sign is WHITE smoke coming from the exhaust that smells like Antifreeze.
Check your exhaust while running, smells sweet and blueish smoke. Overheating, loss of coolant. Do a compression check.
A compression test. If you see white smoke from the exhaust that smells sweet, you have a blown head gasket or cracked head or both.
Are you sure it's a leaking exhaust? If you think it is, then get a new exhaust fitted! But are you sure it isn't diesel smoke coming off the exhaust due to leaking seals on one or more injectors? That's the favorite!
You have a blown head gasket. Open your radiator while the engine is running. You should find exhaust coming from it.
don't ever smell your car's exhaust.
sounds like a blown gasket, allowing coolant to enter the cylinders.
because of the exhaust
The car exhaust smells like the rotten eggs as a result of the hydrogen sulphide. This usually happens, when the engine is not serviced for a long time.
probably an exhaust leak, at or near the exhaust manifold
If what you are decribing is smoke coming from underhood that smells like burnt oil, it may be your valve cover gasket(s) leaking on the hot exhaust manifold. This smell is strong enough to come into the passenger compartment while you drive. It should be repaired. I hope this helps you. Mark