98 cav 2.2L A/C and engine problems?

I have a 98 cavalier 2.2L with recent a/c and engine problems. First it began taking longer to cool down. Now it whines very loudly when a/c is turned on, no noise when it is off. It frequently stalls when it is put in either drive or rev, but only when the a/c is on. It seems to run fine when the a/c is off. Check engine light comes on soon after a/c is turned on. After car is off for a while and restarted, the check engine light will be off. possessed by demons? j/k Any ideas would be appreciated.