I got a 2001 Ford F-350 and for the past 5 years I’ve had the same issues with the A/C but lately it’s gotten worse. At first it will blow ice cold air then about 4-5min later it will get humid in the vehicle if the windows are up and start getting hot till it gives out. Now sometimes if I stomp on it when it starts doing this it will stop it and keep it running cold. Any ideas on what it could be? Summer is back in Las Vegas and I would really like cold air this year.