The refrigerant capacity of all vehicles is measured in either pounds or ounces. The 1994 Ford Mustang’s R134a refrigerant capacity is 2.13 lbs., or 34.08 oz. A recharging station uses an internal scale to precisely measure the amount of R134a introduced to the system. If you are not using a machine, you can estimate the amount of refrigerant introduced into the system by noting the number of ounces contained in each can of refrigerant you add.
The 1994 Mustang’s air-conditioning system has high- and low-pressure sides. The high-pressure side’s pressure should range from 125 to 230 psi, and the low pressure side should range from 25 to 45 psi. You can only check these pressures by using a set of manifold gauges connected to the service ports.