ac problem

[kevinpaigeking]

my 94 q45 stopped blowing cold after a brief overheat. had radiator and waterpump changed the next day. very hot here right now. checked low pressure side of ac and it showed very little pressure. filled it up with r-134 until gauge showed full. ac blew cold until i got on the freeway, then felt as if compressor was off. i have temp set to 65. once i park, begins to get cold. did not have this symptom until day after overheat. i can hear compressor turn off and on when eco button is pressed.

[qship96]

If pressures get too high or low, the triple switch shuts compressor off to save it from damage. Must get accurate HIGH and LOW side pressures under the operating conditions specified in the service manual to even begin figuring this problem out.

I have always felt A/C work is best left in the hands of a true certified A/C tech/shop......way too many owners screw up their system by attempting to fix themselves, and the usual first mistake is to purchase and use a can of refrigerant trying to solve a cooling problem......by randomly adding some amount of refrigerant without knowing the EXACT WEIGHT of refrigerant already in system just makes accurate diagnosis of true problem even more difficult.

The ONLY way to truly know how much refrigerant is in your system is to have it evacuated/vacuumed down/and recharged using the exact amount of ounces of R134 as specced in manual......then you can begin isolating system performance and problems....any shortcut in above method just creates more difficulty in getting the maximum performance out of your system.

[kevinpaigeking]

thanks. i needed a fix on a 105 degree Saturday and assumed the gauge and chart would keep me from hurting the system. should the low side intake get cold when operating properly?