If you add some R134a (sure that all '93 MB used R134a), it will probably just leak out. I guess it depends how big the leak is???
Probably should add some leak detector while refilling the A/C so you can see where it is going.
But make sure the cart used R134a. In one of your posts, you mentioned a '92. They, most likely used R12.
Regards . . . . JimF
'94 S500 Cpe
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