I am fairly sure I overcharged my wifes A/C in her Jetta. Can I connect the hose that came with the recharge kit with the valve closed and then slowly open the valve to bleed off some of the coolant?

 

I already did this and drained off too much. I borrowed gauge set from a friend and checked low and high side pressure. Low side is now marking 42-50 while high side is marking 175 to 200. Based on what I have been told Low should be 32-40 and high should be 200-275. Based on that information a low side of 42-50 with a high of 175 would lead me to think my compressor is bad. Any thoughts on this??

P.S. System is achieving cooling temps of about 15' below ambient.