Due to the efforts of the enviro-wackos*, the R-12 A/C refrigerant that the 91-93 Capris came with was outlawed as being "environmentally damaging". (Allegedly, this heavier-than-air gas magically rises to the upper reaches of the atmosphere and causes holes in the ozone layer. :rolleyes: ) Therefore, since R-12 is no longer available for sale in the US and most of the world, A/C systems must be retrofitted to the new R-134A refrigerant. More money out of your pocket to protect you from nothing.
*It should also be noted that duPont's patent (and therefore their ability to make $ on all R-12 sold) on R-12 expired the same year it was outlawed, and that the replacement, R-134A was developed and patented by duPont. But I'm certain that this fact would have had no bearing on the product being "banned" at that time...
Marty