[robdelorenzo]

Well, this can't be good.
I buttoned everything up and started to fill the coolant tank with distilled water.

As soon as I started the engine, water started flowing out of the overflow hose.
That's the ONLY place that I can see water coming from.
I got on my knees with the rear in the air and looked with a flashlight.

As the engine got warmer, it started to flow more.
I shut it down. I didn't even try to get it up to temperature.
As it was running, I could hear a sucking sound coming from the overflow hole in the tank. I put my finger in the hole and felt suction.

This may be a dumb question, but if the tank can't hold pressure, would it dump into the overflow tube or is the cooling system itself under too much pressure and dumps out coolant as soon as the engine is on?

I don't think it's burping, because it's a steady flow. Not a once in a while thing.
Can the bleeder valve be bad? Would that cause these symptoms?

So the tank may be the problem.
What would cause the overflow to just keep gushing on the other side of the firewall?
Does this mean that the tank is unable to hold pressure and it's bad?
The mechanic told me that the cap vents steam into the overflow hose in case of high pressure.
I have water flowing out of the overflow hose.
What else goes into that overflow hose?
I have yet to find a decent picture that explains the connections on the inside of the firewall and where each hose comes from and goes to.

A pressure test, I know. I don't have one.

The one in there is "The German" one from Pelican and is still under warranty.
I think I was charged about $600 to have it put in.

The real existential dilemma is it's a salvage title Boxster with 145k on it.
How much more $$ do I put in at this point?
If I can drive it to the junk man, I'll get $1400. If they come get it $900.
If I replace the tank, will it last or does it have "hot spots" that are going to crack on me and is the $$ better spent on more reliable car for now?

Ugh.