A/C Troubles

[Mikebear79]

Two things: Why does my car hate me when I turn on the a/c? It almost immediately starts to run rougher and acts likes it wants to die, and sometimes does, while at idle. The compressor doesn’t sound great, kind of making a metallic groaning noise. The system has been converted to r134a, but I want to convert it back to r12. Also, based on the pic below, should I be worried about the copper pipe coming out of the firewall with all that corrosion buildup on it? The system as it stands does blow out cold, but not a strong flow at all. Thanks - Mike

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