Hi Rummings,
Are there any signs of oil in the coolant? Or coolant in the oil?
Is compression ok on all four cylinders?
Have you checked the spark plugs? How do they look?
Petrol and oxygen reacts to CO2 and H2O - i.e. water. So there will always be steam coming out of an exhaust. It is quite visible in cold weather, as you have probably noticed on many occasions.
If you had lots of water entering the exhaust, there could still be some moisture trapped in the silencers, but as the exhaust system becomes very hot, I would think that it would boil off after a few hours drive. How much has it done?
Cheers,
Anders