13330 - Service Update. This bulletin provides a service procedure to address incorrect calibration values in the Active
Fuel Management (AFM) system. These calibration errors can cause the hydraulic lifters to actuate at the wrong time, when the combustion chamber is under high pressure. If this occurs the hydraulic lifter can be damaged and the affected cylinder will no longer operate. To correct this condition, dealers will reprogram these vehicles with a new ECM and TCM calibration.