Why would there be coolant in your exhaust?

catalytic converter converts some oxides to water, so water not a surprise in and of itself. Is there Antifreeze in your exhaust moisture? are you sure it is antifreeze? are you loosing coolant reservoir level at a measurable rate? Coolant only gets into exhaust by way of the cylinder head developing a leak. from the cooling jacket into the exhaust port of a cylinder. if it was leaking into the combustion chamber, you would have coolant in your oil, and the plug would be fouled with scale. possible to attempt a leak seal with K&N Metal Block Seal, if and ONLY if the leak is NOT into a combustion chamber. Or do the right thing and get the head repaired. Or, have your intake gaskets checked for leaks. On the 3.4 the intake gasket can leak coolant into the engine.