Serpentine belt

If your belt is slipping then you need a new belt and a new belt tenisor yours is weak and letting the belt slip. Do you have a floor jack 15mm and 10mm deep sockets ratchet etc?

Let me throw in one thing here. Make sure you haven't overcharged the system because that compressor could be locking up from the extreme pressure.

That is a good point wrench when I have seen those cars overcharged the high/low switch will cycle the compressor off I havent really seen them make the belt slip unless the a/c compressor or a/c clutch locking up. But anything is possible what are your a/c pressures?Also yes you can replace the belt tenisor thru the wheel well you just have to support the engine with a piece of wood between the floor jack and the oil pan. Then remove the upper engine mount and the side splash cover. You then can raise and lower the engine with the floor jack to get to the belt and the top and bottom bolt holding the tenisor in place.

Thats not bad whats the high side read?