2004 Buick Lesabre Custom A/C problems

So i have a 2004 Buick Lesabre that the A/C is somtimes working in. The a/c works fine in cold weather but rarely works in hot weather. If you press the brake the a/c compressor comes on for 30 seconds then shuts off. Fans will come on but shut off after 30 seconds. We have changed the coolant temp sensor and the HVAC pressure transducer sensor and the relays. We have checked the freon and it was full at first but its lower now, more on that in a second. We noticed when checking the gage that when the compressor is on the gage is normal but slowly rises then get too high and shuts off, so we let some pressure out and the compressor came on but built pressure again and shut off, once again the a/c was cold cold so freon levels where normal till we removed some, now its luke warm so the levels are low but the levels where not the issue to begin with. The car will run hot after a while because the fans cant stay on because the whole system keeps getting shut down because of the unknown problem. What could be causing the problems? No codes are showing for A/C issues, only codes are 02 sensors which i plan on changing. The only other thing on the dash is the abs light, brake light, and traction control light, so something is wrong with the abs system but idk what. Could the abs system affect the a/c somehow? Especially since pressing the brake causes the compressor to kick on? I dont think its the compressor itself since it works fine in cooler weather, im talking 70"s and below. Once it hits over 80 its hot air.