I have a 97' Nissan Altima that makes this horrible loud whiny squeaking noise. It seems to be triggered by accelerating when the AC is on and also stops when I turn the AC off. I live in south FL so I need the AC. Please, please help me out.

I have a 97' Nissan Altima that makes this horrible loud whiny squeaking noise. It seems to be triggered by accelerating when the AC is on and also stops when I turn the AC off. I live in south FL so I need the AC. Please, please help me out.
The easy things you can check are that both radiator cooling fans turn as soon as the A/C is turned on and the condition of your belt. Your belt could be worn or damaged from coolant or oil causing it to slip and squeak at the A/C compressor when you accelerate. The other is inspect the fins on the condensor possibly flattened out and blocking air flow. The condensor looks similar to the radiator and mounts in front of the radiator. The most likely cause is too much freon in the A/C system. There is no way to know if it is overcharged or guess how much to remove without pressure gauges. The correct repair procedure is to remove all of the freon, evacuate with a vacuum pump, and measure the correct wieght added to the system. Too much freon or restricted air cause the presure to go higher making the A/C compressor work harder and more difficult for the belt to accelerate the compressor when the engine accelerates so the belt slips and squeaks. Overcharged A/C systems don't cool as well as properly charged systems and waste fuel. When you turn the A/C off the compressor stops pumping so the belt doesn't slip and squeak.