90% of the time water/steam out the exhaust is the head gasket the other 10% it is intake gasket related.
The bigger question is, as it seems to run okay, how long have you actually ran it? It could simply be water/coolant that got into the system from an intake leak and it has not "burned off" yet because the exhaust has not gotten hot enough for long enough to steam it all out.
Are you seeing coolant loss?
Go get a cooling system pressure tester. Run the test and see if the system holds pressure. If it does and you do not see the coolant level dropping then it is likely remaining water.
If however it will not hold pressure and you see coolant use, it is one or both head gaskets or worse cracked head(s) block.
Then run the combustion gas test to see if you still have a problem.
When you pull the plugs out, look at them as you pull them. If you find one or two that are very clean you know where the water was/is going.
Saturday, September 9th, 2017 AT 5:38 PM