What is the reason for charging the system? Did something fail and you replaced it or does the system just not operate? Has the system been open (ie lines disconnected, leaked down over time, component replaced)
1994 should take R134A, but as it sounds like you have never worked with it before you may want to take it to a shop. The reason being that you need a few tools if you plan on doing it correctly, and if you are not 100% sure of what you are doing you can easily get injured or damage components on the vehicle.
Tool wise you need a set of refrigerant gauges. A vacuum pump for AC work, the proper hoses, and if the system leaked down a UV light and dye. And a very sensitive scale that can weigh the charge as you fill the system.
Plus the R134A. Auto parts stores will have that. As to the amount, that will be on a tag on the vehicle.
You charge the system through the low pressure port.
If you are sure the system is okay and has no leaks there is this method.
Saturday, July 22nd, 2017 AT 4:31 PM