TankTread

Thanks guys for the assistance in helping fix my issue. I played around with the pressure on the low pressure side of the system and made sure to check the pressure and add refrigerant with the car already at operating temperature. I am not sure if this is a rule of thumb when doing AC stuff but when the car was at operating temperature the pressure was registering overpressurized at the low side port. I bled off some refrigerant until the needle was just inside the high range line at the ambient temperature of the day. Everything has worked without a hitch since. I hope I don't have to repost if we get a day over 95 degrees.

I added refrigerant today. The AC was very cold and was in the correct operating pressure at the low side port for the temperature it was today. The needle on the gauge sat at the high side of the 10psi range for the ambient temp for the day. When I pulled out onto the street and started to drive the AC air turned humid and warm like outside air. I know the pressure on the low side is good. To Meier's point, I was not able to check the high side pressure. Does this help anyone further diagnose my issue? I should say that the pressure is in range when the compressor is running and climbs into the red area of "overpressurized" a few seconds after the compressor shuts off.

I can agree with you on rapid cycling "usually" being from low pressure or refrigerant charge. In my case I do not think I am low being I put a full can of refrigerant in, the gauge red high on the refrigerant level and I had to purge out of the low pressure side a few times to get the AC compressor to even stay on long enough to cool the cabin. Can there be another system component that's affected by the high temps outside that would cause the AC to drop out of operation while running? When the AC drops out it goes into the rapid cycling mode while driving. If its cooler outside I will have no issues.

I thought I'd post up on this thread on some issues I've been having with my AC in an attempt to keep the AC conversation in one place. I drive the same route to work every day. Weather is about the only changes the car undergoes between the air conditioning working and it not working. I have linked the air conditioning problems to what seems to be the outside ambient temperature. During highway driving the air conditioning is cold and works well. Occasionally there is a quick and short lived "warm up" in the air coming out of the vents. I think this may be an attempt for the automatic AC controller attempting to maintain the set temperature. This behavior was pretty consistent for temperatures below 90 degrees Farenheit. Just to be sure that it was controller related and not refrigerant related I bought a can of r134a fitted with a pressure gauge and 'topped off' the system. After closing the valve and reading the pressure gauge it was evident I got a little too much refrigerant in the system. The system, running while filling the refrigerant, started to cycle the compressor on and off 1 second at a time. I then bled some of the pressure off a bit until the compressor ran in normal cycle times. The air conditioning system seemed to work normally throughout temperatures up to 90 degrees. Things changed, however, when the temperature outside crept up over 90 degrees. During the same highway driving the air conditioning would "drop out" after running well for 10-15 minutes. The compressor would start the rapid cycling at the same time the air conditioning went into this mode. Air temperatures out of the vents become warm and humid in this mode. Occasionally the AC button can be cycled and I may get lucky for a short time with some cold air. Eventually it goes back to warm and humid. This past week we experienced above normal temps near 100 degrees. I again purged some of the refrigerant to lower the pressure a bit more. I didn't notice a big difference in the behavior of the system. I can still get cold air for around 10-15 minutes of the drive and then the car goes to the quick cycle and warm humid air out the vents. This may be a case of still having too much refrigerant in the system but I also am thinking a possible faulty pressure switch. I consider the switch because at idle the air isn't as cold as when the car is at operating rpm. I apologize for the long winded post but I wanted to throw out some of my experiences that may help others chase their symptoms to a solution. I don't really have a lot to offer on the system since I'm not a HVAC guy. I can say that I don't have a leak in the system although this thread has seemed to prove this as the catch all answer.

Local semi newbie here in Akron area with a OBP LGT Sedan. Just got the windows tinted for Father's day. It was my "instead of" dinner and a card...not a bad deal!