18-108-20

Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs):P0420 - Catalyst System Efficiency Below Threshold Bank 1 P0430 - Catalyst System Efficiency Below Threshold Bank 2. Customers may describe the following:Hearing a pre-detonation noise (Spark Knock) sound in the engine during acceleration.