Air blowing from vents is barely cool and A/C compressor is cycling rapidly

1997 FORD CROWN VICTORIA
140,000 MILES • 4.6L • V8
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MECHANIC’S KID
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With ambient temperature of 82F and humidity of 74% the low side is 40-42psi and high side is 160-165psi. (Lower # compressor cycled off and higher # cycled on.) Static pressure after its turned off is almost equal at 115 and 120. DTC 00 No codes.
High side seems low to me but everything I’ve found indicates low side is okay.
I’m afraid of overcharging the system. But should I add refrigerant anyway?
Jun 19, 2019 at 12:08 PM
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ASEMASTER6371
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Good afternoon,

The low side is the issue. It is too high. It should be 25-30 lbs. 42 is rushing the Freon through the evaporator too fast and that means cool, not cold air.

The fact the static is not the same confirms it. They should be exactly equal.

You need an expansion valve and a dryer.

Roy
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Jun 19, 2019 at 1:19 PM
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MECHANIC’S KID
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Thanks Roy for your reply and advise. I had wondered about the expansion value and was hoping it’s not the compressor. I think I may be solo on this one.
I’d love nothing more than to ask my Daddy these questions. He was a Ford certified mechanic with 40+ years. We lost him in 1998 and this “Green Hornet” was his last car and he only had her 10 months. So she’s special to me. Mom kept her in good shape until she was left parked for a few years. Since last summer my husband and I have replaced the fuel pump, plugs and ignition coils. We’ve worked on almost all her windows too replacing 2 regulators and rebuilt the window motors. Now I just want it to be comfortable enough to drive and get a wash!
Thanks again
Mary, Mechanic’s Kid (youngest daughter)
Jun 19, 2019 at 5:33 PM
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ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
Jun 19, 2019 at 5:42 PM