GM Service Manual Online
For 1990-2009 cars only

The efficient operation and life of the A/C system depends on the chemical stability of the refrigeration system. Contamination with dirt, air, or moisture lead to chemical instability, resulting in the following conditions:

    • Unstable pressure-temperature relationships
    • Interior corrosion
    • Premature component wear
    • Premature component failure

Observe the following general practices in order to ensure the chemical stability of the system:

    • Before breaking a refrigerant connection, wipe away any dirt or oil. This will reduce the risk of contamination. Immediately cap, plug, or tape both sides of the connection.
    • Keep all tools clean and dry, including the manifold gage set and any replacement parts.
    • When adding PAG oil, ensure that the transfer device and the container are clean and dry.
    • Set up all necessary tools, cleaners, etc., before opening the A/C system. Do not leave the A/C system open any longer than is absolutely necessary.
    • Evacuate the A/C system after opening and before recharging.
    • All service parts are dehydrated and sealed prior to shipping. Do not open packaging until the moment of installation. Keep parts at room temperature before uncapping. This prevents water condensation from the air entering the system. Reseal any parts as soon as possible.