A/C System Performance
- Place vehicle out of direct sun light. 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.
- Turn mode selector to VENT position, blower speed selector to high speed, and temperature selector to full cold position. Run engine at 2,000 RPM for 5 minutes to allow A/C system to stabilize. 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, at 2,000 RPM, should be within correct range. See A/C SYSTEM PERFORMANCE PRESSURE SPECIFICATIONS table. Discharge air temperature should be about 20°F (7°C) cooler than ambient air temperature on a normally operating system. If operation is not as described, see procedures in A/C-HEATER SYSTEM TROUBLE SHOOTING - MANUAL article.
A/C SYSTEM PERFORMANCE PRESSURE SPECIFICATIONS
| Ambient Temp. °F (°C) | High Side psi (kg/cm2 ) | Low Side psi (kg/cm2 ) |
|---|---|---|
| 70 (21) | 150-290 (10.5-20.4) | 22-40 (1.5-2.8) |
| 80 (27) | 150-350 (10.5-24.6) | 25-45 (1.7-3.2) |
| 90 (32) | 200-350 (14.1-24.6) | 30-50 (2.1-3.5) |
| 100 (38) | 250-400 (17.5-28.1) | 35-60 (2.5-4.2) |