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A/C System Performance

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  1. Park vehicle in shaded area. Ventilate interior. Vent exhaust. Install manifold gauge set. Measure and record ambient temperature and relative humidity. Close doors and windows. Set mode control to normal A/C. Operate blower control at high speed, and set temperature control to full cold position. Insert thermometer into right center outlet.
  2. Set shift lever to Park or Neutral position. Run engine at 2000 RPM until outlet air reaches lowest temperature. Record outlet temperature, and high-side and low-side pressures. Turn engine off. Compare readings with specifications. See A/C PERFORMANCE SPECIFICATIONS  table.
A/C PERFORMANCE SPECIFICATIONS

Ambient Temp. °F (°C) (1) (2)Low-Side Pressure psi (kg/cm2 ) (2)High-Side Pressure psi (kg/cm2 ) (3)Outlet Temp. °F (°C)
70 (21) 32 (2.2) 240 (16.9) 50 (10)
80 (27) 37 (2.6) 290 (20.4) 56 (13)
90 (32) 44 (3.1) 340 (23.9) 63 (17)
100 (38) 55 (3.9) 395 (27.8) 75 (24)
(1) Measured at 60 percent relative humidity.
(2) Maximum pressure.
(3) Maximum temperature.