Roadster or coupe? SRT? I believe it was raining in SF lately; water can find its way into the area in the rear of the car near the air pump. If you have moisture back there it will exhibit the symptoms you describe.

You will find all the info you need in the TSB and How to Articles topic. Specifically look here: Sticky: Index of Crossfire problems and repairs (Multi-page thread 1 2 3 ... Last Page) and then scan down the screen to the Body section and see "Water in Trunk"

Try using the search box with "water in trunk" it might get you there quicker. Also search for SKREEM module