Trying to add refrigerant to AC?

Im trying to add refrigerate so ac will blow cold.I 100% located low pressure port and I let all the old refrigerate out. When I go to add new refrigerate, it instantly reads that it is full. Pressure gauge is brand new and ac is set on max while car is running. Someone help.

Yep, this happens when the fitting on the low side is no attached fully or the knob on the top of the fitting is not closed completely, here is a video to show you how.

https://www.youtube.com/watch?v=uZrQCGwXfek&t=1s&pp=0gcJCUwLAYcqIYzv

Please upload a short video in your response of the problem, so I can see what's going on

Please let me know what happens.

Im using a can that screws onto the pressure gauge. Doni need to open and close it continuously?? Also. When I took the gauge out of the low pressure, air came out of it for about 20 seconds. Not sure if that is normal

Hello, I dont mean to interrupt, but there was a warning out about these small refill cans you can get an autozone,walmart etc. They were finding almost 50% of those small cans were not refrigerant at all. They were fake shipped from over seas. They do not allow you to know if you have the correct amount either.
When you took the gauge off, and refrigerant came out, that means air went in.

If you want to be a 100% sure on your system working and more importantly lasting, I highly recommend getting the entire AC system evacuated, having them pull a vacuum on it to get all the air and moisture out, as well as check for leaks and then refilled with the exact amount. You run a risk of having more problems and probably not making it through this summer with that system. And its way too hot to be without AC. I know it costs a little bit for them to put the machine on it to empty and refill it, but it will save future headaches.