I have a 99 cadillac deville. When I turn on the ac, the compressor clutch cycles on and off continuously and the air is not real cold. I purchased a can of 134 and a hose and gauge set to add 134 to the system. When I add the 134 the pressure rises until the compressor clutch comes on then the pressure drops dramatically until the compressor clutch stops. When the clutch stops the pressure will rise again till it gets to a point when the clutch comes on again. The process is repeated over and over again. I think that I have a leak somewhere. Are there any suggestions

 

buy the 134 with leak detector dye mixed with it. then recharge the system. a week later have a shop check it for any signs of dye leakage then fix the leak.