QuestionQUESTION: Hello, my wifes 01 Olds Aurora is not cooling as expected. On a 90 degree day, it's about 60 - 65 degrees at middle vent. The pressures are about 50 on the low side and 175 -200 on high side at idle. Two things are throwing me off.
First is the suction line from the evaporator to compressor is cold and is sweating, so it appears to be working correctly. Second thing is the service ports are not in the normal place. The high side service port is between the condensor and expansion valve and the low side is between the expansion valve and evaporator. I usually see them between the evap and compressor on low side and between the compressor and condesnor on the high side. With the service ports in a different location, won't the pressure readings be different?
I've checked the cooling fans and they work OK, so I'm not sure if the compressor is not "sucking" like it should or if the expansion valve (which is electrically controlled) is open more then it should or maybe it's not of that...Joe.
ANSWER: Hi Joe
Need to know a little bit more. Has this vehicle been serviced before and if so did they vacuum the system properly. Your service port are in the correct place. It would not make a difference on your readings.
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QUESTION: The car has not been serviced since I owned it, so I'm not sure if the system has been vacuumed. could there be air in the system? Also, I'm confused about the port placement. For example, wouldn't the high side pressure reading be higher before it hits the condenser rather then after the condenser, after some of the heat has been removed from the cooling fan? Thats why I'm confused about reading the pressure readings. On all the cars I have worked on, the service ports have always been between the compressor and the evaporator and the compressor and the condenser. thanks for your help.
AnswerHi Joe
the aurora's have an electronic orifice tube (solenoid) to control the flow of freon. That may be what you see different. On an orifice type system you measure high side from condensor to orifice and on an exp valve system you measure high side from compressor to drier or condensor which is usually close by. depending on your ambient temp. your readings can go as high as 50 or 55. I would put in a little more freon and raise your high to about 250-275 if your ambient pressure is 90 degrees or higher.
