Cadillac Repair: air conditioner, electronic leak detector, r 134a

Question
QUESTION: My 1998 Cadillac deVille's airconditioner no longer blows cold air.  It blows but it sometimes does not stay on "auto" an jumps to "econ".  When it does this I get the message "a/c - refrig low. My local trusted mechanic has tried to fix it twice. Should I take it to Cadillac? Will it cost an arm and a leg, a foot and a hand??????Hope you can help.  Stacey

ANSWER: Ask your mechanic what type of freon he is installing and let me know.

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QUESTION: Hi I do not know what type of freon he used.  If you tell me the type I need I will tell him to get it. Thank you, Stacey

Answer
What you have is a leak in your A/C system and all the freon type R-134a is leaking out due to this leak that apparently your mechanic cannot find and fix.

In order to fix this problem you need to find a reputable A/C facility who will add a can of freon to your system and then they will use an electronic leak detector to find and fix the leak.