hello again. I'm having problem with my car the car is fine and smooth when ac is off but when I turn on the AC I hear like whine noise and the rpm is not so smooth speacily when it goes down example from 3k rpm to 1 k rpm I can see the rpm needle shaking little bit . is that serious problem? what to do ?

btw I'm running aftermarket ignition coils
2002 xj8 .

thanks.

 

could it be overcharged AC system?