they have elected a pope? in cold weather it is normal to see white smoke coming out of your tailpipe. the one you have to worry about is the black or the blue smoke
White smoke is a sign that coolant is entering the combustion chamber. This is commonly caused by a cracked head or blown head gasket or both. This is a very serious condition that requires you STOP...
White smoke from the exhaust is a symptom of coolant entering the combustion chamber. This is normally caused by a blown head gasket or a cracked head. Stop driving the car immediately as severe...
Is the white smoke steam or oil vapor? If it's steam, it just needs to warm up, if it's oil vapor it's probably pretty serious. Same with the knocking. It could be timing or it could be a rod bearing...