another a/c problem
 

I have a 95 933 and have a refrigerant leak. The other day when I switched from the heater to a/c I heard a hissing noise from behind the dash. I immediately suspected a refrigerant leak, which was confirmed when the a/c would not produce any cold air. Anyone have any suggestions where I should start to run this one down? Thanks for any help!

Expansion valve or evaporator core

AFJ

What should I be looking for in the area of leak, will there be an oil residue?

The hissing noise might have been one of the servos actuating. That’s not a big deal.

I think to find small AC leaks, they put a dye in the refrigerant. Sometimes it is UV sensitive. A black light is used to find the leak.

For a good reference, go here: http://www.porsche964.co.uk/

Click on “Technical” then “electrical repairs and modifications” and then the last one: “964 heat and vento servos.” The 964 and 993 are very similar in this area.