03 WRX milage unknown. Runs fine but it is bellowing steam from the turbo area. Looks like I am seeing some moisture bubbling at the up pipe connection to the turbo also. The car has been sitting for about a year so could condensation have settled in the low point of the header?

When you installed that replacement TD04, did you replace the coolant lines? They get old and cracked like vacuum lines.

Did you ensure the coolant copper crush washers were in good condition on BOTH sides of the banjo bolts? Many state to use new washers, but I've never had an issue reusing them (many times).

 

The bubbling from the uppipe indicates a exhaust leak? Remember that the ICE process produces H2O. 

try changing your intake/exhaust gaskets all around?

I do need the exhaust gasket. The copper washers all looked good. I can't figure where that much moisture would come from