Temperature turned 83 F here in CT this week, so I turned the A/C on, for over 10 minutes I didn't feel any cold air coming from the vent. When arrived home, parked the car, cool it down, use a gauge to measure, 100 PSI!!!

I'm 100% it's the low pressure port, so which could be at culprit? And what should I do? release them all and recharge?
Advice is greatly appreciated. Thanks, guys!
Sincerely,
Lei
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01' 3.0i E53 (M54) with 164,000 miles

07' 3.0si E83 (N52) with 134,000 miles

08' 3.0si E70 (N52) with 91,000 miles