I have a 98 Civic that blows cool air but not real cold air. I have a thermometer in the vent that will go down to the top of the green line which is about 45 F. The temperature doesn't change with the blower fan on high or whether or not I am driving or sitting still. I checked the pressure at idle with the AC on max and I am getting 28 on the low side and around 200 on the high side. I have a friend with a 97 honda civic that will blow approximately 38 F with the same thermometer so I am just wondering what may be restricting it from blowing colder than the 45 F that I am currently getting. Thanks ahead of time.

 

If your compressor is cycling on and off slowly as you drive, the refrigeration system is fine. Two factors can cause higher vent temps. The first one, real common on Civics, is reheating of the air in the heater core. The water valve on the firewall must be fully closed when you set the dash control to full cold. The other potential cause, more obscure, is the evaporator temperature control cycling the compressor off sooner than it should.

 

Where would the evaporator temperature control switch be located at? Is it on top of the receiver drier? Thanks and I will check to see if the heater hose valve is shutting off completely this evening.

 

At about 85F with a hot engine idling to spec, my 97 Civic refrigerant pressures are:

High side = 205 PSI; Low side = 42 PSI

My A/C works fine, so your low side pressure may be too low: