A/c Issue !!!!!! ??????

I Have A 91 Gc 3.3 2wd, When I Turn On The A/c It Comes On Ok But Not As Powerful/cold, Once I Give The Van Gas I Hear The A/c Kick In With More Force And A/c Is Felt Via The Vent Blowing Colder Air .

As I Accelerate To Fast Speed It Losses A/c Force I Have To Release The Gas Pedal And Them Step On It Again And It Will Kick In Again

Can Someone Explain Or Comment On This

Thanks
Dayalalito

your AC system probablly needs a recharge