This bulletin applies to 2008-2010 Dodge Charger and Magnum vehicles, equipped with the 2.7L engine and 4-speed automatic transmission. A rough idle on startup with ambient temperatures below 50 degrees Fahrenheit may be experienced.
This condition may most likely happen during summer and fall seasons when summer blend fuels are in use. The condition is not noticeable after the engine warms up to operating temperature.
To correct this condition, the PCM software was changed to add additional fuel and increase spark advance during the warm-up cycle.
This bulletin involves flash reprogramming the powertrain control module with new software. Software release 10.04 or higher is required.
1. Reprogram the PCM with the latest software. Follow the detailed procedures available in DealerCONNECT/TechCONNECT. After PCM reprogramming, clear any DTCs that may have been set in other modules due to reprogramming. The wiTECH application will automatically present all DTCs after the flash and allow the tech to clear them.