AC ports and readings?

[panteramatt]

My ac is just blowing cool and its usually pretty cold. I believe I need some refrigerant but want to check it with my gauges. Wheres the low and high ports located on a 7.3 and what readings should I get? Do I check it warm and running the ac?

[7.3HeavyHauler]

both are on the passenger side, one is right in front of you if your standing in front of the truck and the other is under your map sensor, they both have screw on caps, i have a hard time getting the connector onto the low side (under the map sensor), use a screwdriver and remove one screw from the map sensor and rotate it out of your way. i believe the compressor is supposed to disengage around 30 - 35 not sure about the engage pressure but someone will chime up.

[panteramatt]

Ok. The 2 ports are different sizes and my gauge only fits the small on on the condensor. (low?) Anyway, it read 95 psi and its about 80 outside. Is that good?

[tonyf250]

The compressor is not engaged and running if it is at 95 psi. It is very likely that the refrigerant is low and not turning the compressor on.

[panteramatt]

Ok, so I have to check it with the ac on? I believe the compressor turns on casue it does get very cool just not as cold as it should be or used to be.

[tonyf250]

Yes turn on the A/C to max and look at the pressures.