Pressures for air conditioning on 1991 Chevy lumina
2 Answers
At 75° ambient temperature low side 35-45psi, high side 120-140psi. The hotter the ambient air, the higher the pressures will (should) be. Your Lumina was manufactured with R12 Freon, and is not for sale to the public.
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stephend103 answered 8 years ago
I would suggest low side at 30-35 psi and high side 150- 160 psi. But the pressures are relative to outside temp, condenser fan operation, and engine speed. The pressures I noted would be on a warm day, condenser fan on, and engine at 1200-1500 rpm.
