A/C System Performance
WARNING: This page is about a different car, the 1998 Chevrolet Monte Carlo and 1998 Chevrolet Lumina. However, it is still accessible from the selected car via links, so may be relevant.
- Place vehicle out of direct sunlight. Ensure ambient air temperature is 70-90°F (21-32°C). Install A/C manifold gauge set. Close all vehicle doors and windows.
- Start engine and allow it to reach normal operating temperature. Select MAX mode and set temperature to full cold setting. Run engine for 5 minutes to allow A/C system to stabilize. Blower motor should run at high speed and cold air should flow from dash registers. Record high-side and low-side pressures.
- Feel liquid line on both sides of expansion tube. Temperature between sides should be noticeably different. Pressure readings should be within correct range. See A/C SYSTEM PERFORMANCE PRESSURE SPECIFICATIONS table. Normal discharge air temperature for a properly functioning A/C system is about 20°F (7°C) cooler than ambient air temperature.
A/C SYSTEM PERFORMANCE PRESSURE SPECIFICATIONS (1)
| Ambient Temp. °F (°C) | High Side psi (kg/cm2 ) | Low Side psi (kg/cm2 ) | ||
|---|---|---|---|---|
| 70 (21) | 290 (20.4) | 37 (2.6) | ||
| 80 (27) | 340 (23.9) | 42 (3.0) | ||
| 90 (32) | 390 (27.4) | 49 (3.4) | ||
| 100 (38) | 445 (32.0) | 60 (4.2) | ||
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