NikosXJ2000

I'm new to this forum, never posted before, but have been reading/viewing religiously for quite a while. I hope someone can help me, or I may have to set my son's cherokee on fire! I have a 2000 Cherokee ltd, bought it about a year ago and it has had constant issues. The latest, it has started to stall when coming to a stop. Took it to the dealer, they said it was probably the TPS or the Air Control Motor/Valve. They wanted $600 to replace both, so I instead bought the parts at advanced auto for like $90 and put them in myslef. Idle was initially very high, then came down once the computer adjusted I guess. However, now I have some God awful sound coming from the A/C compressor, sometimes when the clutch engages, and other times when its free.. It is the worste noise I have ever heard, and the idle seems to be close to stalling again... Is it possible that the A/C compressor or clutch is causing such a drag on the motor that 'that' is what is making it stall? Please someone help, I'm at the end of my rope with this thing, I just put over $3000 into it this year, and although it looks and drives amazing still, it is turning into a huge investment! thanks in advance.