I have a 1996 Accord EX, with 344K. I have owned the car for 4 years and the air conditioner has never work well. Today I got the proper adapters to hook up pressure gauges to both the high and low sides. The conditions that we started with were:

Ambient temp: 93 deg F. (In front of the condenser)
Engine speed: 1500 RPM
Low pressure: 22 PSI
High Pressure: 210 PSI
Temp at the center vent: 64 deg F. (Blower on High)

It looked as if the low pressure side was down, so I added 11oz. of R134a. This changed the system pressure's at the following:

Ambient temp: 93 deg F. (In front of the condenser)
Engine speed: 1500 RPM
Low pressure: 32 PSI
High Pressure: 260 PSI
Temp at the center vent: 62 deg F. (Blower on High)

I am wondering why the evaporator did not get any cooler I suspect a faulty expansion valve, but I am not sure. Any help would be greatly appreciated.

Thanks!