Larry,
The gauges read zero (no charge)
I charged up the system with nitrogen, and did the bubbles test (every single fitting in the engine compartment up to the expansion valve). No bubbles anywhere.
I had a set of gauges connected as I was spraying the fittings, and I could tell the leak was substantial (pressure was dropping at the rate of 1 psi every 3 minutes). The only place not checked was the evaporator itself (hence my assumption). Now I am considering charging it up with dye. If I see any around the vents, I will know for sure is the evaporator.
What do you think of that approach?
I gratefully accept any suggestions you may have on the troubleshooting and repair (I know some AC basics, but it is not my area of expertise).

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1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car
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