300D A/C strike 3

[Crappy Gas Pipe]

1984 Mbz 300D Turbo. 226k GreaseCar
27k miles ago when I bought the car to grease it, it had no belt on the A/C compressor. I had my indy put in a new A/C Compressor, Receiver drier, temp sensor the works. It ran poorly for several months and he added more R134a. Not impressed for some more months and then it blow up. Freon all over the left side of the car. $880 later its fixed again, this time by a Local Auto Shop. The old compressor was out of its 60 day warrantee and the new part is different now. More expensive. It works OK at highways speeds. Took the cardboard off the grill but AC is still just above poor. have to put some towels on the dash to stop defroster. . Does the button to the right of Defrost use the vents by the feet too? Those don't work. Why is this car on self destruct mode? Should I dump it before the AC goes again, next year?