GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1998 🢒 Park Avenue 🢒 HVAC 🢒 HVAC Systems - Automatic 🢒 System Performance Test

    Important: Be sure to record the relative humidity and ambient temperature conditions at the time of the test.

  1. Park the vehicle inside or in the shade. The ambient temperature must be at least 16° C (60° F).
  2. Open the windows to ventilate the interior.
  3. Vent the engine exhaust.
  4. Open the hood and install the J 39183-C .
  5. Record the ambient temperature where the vehicle is parked.
  6. Record the relative humidity. Use a psychrometer or consult the local weather bureau.
  7. Close the doors, windows and lower the hood.
  8. Set the A/C control assembly to MAX mode with the blower speed set to high and the temperature to full cold.Ensure the vent button LED is not illuminated
  9. Open the A/C air outlet deflectors.
  10. Place a thermometer in the right center A/C outlet.
  11. Place the transaxle in PARK and start the engine, and let it idle.
  12. Run the A/C system until the outlet air reaches a stabalized temperature (about 3 minutes).
  13. Record the outlet air temperature and the high side and low side pressures.
  14. Turn the engine off and compare the readings with the data in the A/C Performance Table. Normally operating A/C systems should not exceed levels shown.
  15. If the readings exceed the table limits, refer to High Side vs. Low Side Pressure Table and Gray Area Diagnosis and Service in Cooling Insufficient.
  16. If you were sent here from a DTC diagnostic table be sure to clear the DTC upon completion.

Air Conditioning Performance Table

Temperature

Humidity

Low Gauge Pressure

High Gauge Pressure

Center Outlet Temperature

21°-27°C (70°- 80°F)

Less than 50%

165-234 kPa (24- 34  psi)

793-1310 kPa (115-190 psi)

3°-9-C (38°-34°F)

More than 50%

172-255 kPa (25- 37  psi)

793-1379 kPa (115-200 psi)

4°-13°C (40°- 55°F)

27°-33°C (80°- 90°F)

Less than 50%

193-262 kPa (28- 38  psi)

965-1482 kPa (140-215 psi)

3°-13°C (38°- 55°F)

More than 50%

207-276 kPa (30- 40  psi)

1034-1620 kPa (150-235 psi)

7°-18°C (45°- 65°F)

33°-38°C (90°- 100°F)

Less than 40%

234-296 kPa (34- 43  psi)

1138-1793 kPa (165-260 psi)

7°-17°C (45°- 63°F)

More than 40%

251-331 kPa (36- 48  psi)

1276-1862 kPa (185-270 psi)

13°-20°C (55°- 68°F)

38°-44°C (100°- 110°F)

Less than 20%

276-338 kPa (40- 49  psi)

1448-2000 kPa (210-290 psi)

12°-18°C (53°- 64°F)

More than 20%

296-359 kPa (43- 52  psi)

1517-2137 kPa (220-310 psi)

14°-21°C (58°- 70°F)