Under the air filter compartment.
Connect the Freon bottle to the low pressure port on your air conditioning compressor. Release the Freon into the compressor. The purchase of a Freon recharge kit will make the process quite simple.
On the accumulator.
No. You are looking at the wrong port. If you are looking down at the port you see, look past it to the left, beneath the air cleaner.
That would be the low pressure service port and it should be located on the receiver/dryer.
The recharge port is on the larger AC pipe
The low side pressure port for the 1999 Monte Carlo should be on a pipe against the firewall. It is just to the left of the Dipstick.
The 1999 Chevy Lumina A/C service ports are located on the drivers side of the vehicle in the front, right next to the battery, which is located under the windshield washer reservoir, it will kindof take some contorting to get to it, but that's where GM put it
Its located on the top of the a/c compressor..................
Recharging the air conditioning is simple with a recharge kit. Connects the Freon bottle to the recharge port on the air conditioner compressor. Release the Freon into the compressor.
The AC low side service port on a 1999 Chevy Astro van is located next to the firewall. It is the port that is closest to the evaporator.
Well, honey, first off, you're gonna need to locate the low-pressure port on the AC system, usually found near the firewall. Then, you'll need to connect a refrigerant gauge and a can of R134a refrigerant to the port. Start the car, turn the AC on high, and slowly add refrigerant until the gauge reads in the correct range. Just be sure to follow the instructions on the can and wear some gloves, unless you want frostbite on your hands.
On my retrofitted to R134-A the fill valve is underneath the airbox. You have to take it out to get to it.