Problems with air conditioning. 2000 gmc sierra pick up, ac is slowly going out. works a little sometimes and doesn't work at all other times. can you tell me the problem thank you

I have a 2000 GMC Savana Van SLT with front and rear AC/Heat. My front would blow hot while the rear blew cold with AC on. It turned out to be low on Freon. It's hard to know if you have the right amount of freon installed because pressures vary depending on the ambient temperatures. So the best way is to remove all the freon then reinstall the recommended amount as listed on the evaporator housing near the firewall. This worked fine for me... works like new after installing the correct amount of freon.

PUT IN CORRECT AIR TIRE PRESSURE.YOU CAN DRIVE VECHICLE 25 MILES PER HOUR FOR 2 MINUTES ON A LONG BACK ROAD.THE TPMS SENSOR WILL AUTOMATICALLY RESET.AND THE CHECK AIR PRESSURE LIGHT WILL TURN OFF.

you need to check the grips of the AC and other things . make them tight.. n check fuses. not a big problem.

Hello, this is the instructions for replacing the a/c belt.

Remove the accessory drive belt.

Rotate the air conditioning (A/C) drive belt tensioner clockwise in order to relieve the belt tension.

Remove the A/C drive belt.

You HVAC unit is not getting the heat from your engine coolant. A valve is stuck or there is blockage in the heat exchanger core. I'm assuming you fan and vent divertors/Controls are working correctly. Does AC work?

There are 2 bolts that hold the tensioner to the engine. The pulley is part of the assembly when bought at a dealership.

I'm not sure if I understand you correctly. Does the air conditioning works properly it's just the sound problem and did it happens suddenly?
For the strange sound, it could be normal and not.
I imagine the sound comes from the exchange pressure between the low pressure and high pressure.
To fix or knowing what is wrong you will have to get AC/pressure gauge install on AC/pressure tap under the hood and sync the compressor engaging clutch if it happens at the same time that the sound you are talking about.
Pretty hard to tell online without earing it. But I ever listen to a sound similar to that.

hope it helps

It sounds like you either have an condensor fan problem or low freon. The condensor fan is near the radiator. In some cases the radiator fan doubles as the condensor fan. So look there too.

you need the tempature blend door motor. My 01 silverado had this issue about 1 1/2 years before i was tired of messing with it they are not hard to replace. The cover (if it is still on) for passenger side floor ducts needs to be removed and the motor is near the right side of "hump" (trans tunnel) mounted horisontial with the armature pointing upwards.

Need to have your HVAC system scanned to determine what has failed in that system. Possible blend door for drivers side or maybe the system just needs recalibrated.