GM Service Manual Online
For 1990-2009 cars only

Begin the system diagnosis by reviewing the:

    â€¢  Disassembled Views
    â€¢  Engine Component Description
    â€¢  Lubrication Description - Main Pressure Below 55 psi with Cylinder Deactivation (Active Fuel Management) Off
    â€¢  Lubrication Description - Main Pressure Above 55 psi with Cylinder Deactivation (Active Fuel Management) Off
    â€¢  Lubrication Description - Main Pressure Below 55 psi with Cylinder Deactivation (Active Fuel Management) On
    â€¢  Lubrication Description - Main Pressure Above 55 psi with Cylinder Deactivation (Active Fuel Management) On
    â€¢  Cylinder Deactivation (Active Fuel Management) System Description
    â€¢  Drive Belt System Description

Reviewing the description and operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms - Engine Mechanical in order to identify the correct procedure for diagnosing the system and where the procedure is located.