I am very new to Beetles and have come across a problem that I cannot diagnose. When I started the car this morning (it was very damp and had been raining ) it idled very rough and coughed and sputtered at anything below 2000 rpm. It was low on fuel so I added some "heat" to absorb any water due to condensation, but the rough idle still continues. I checked for codes and there was nothing present. Could this be a moisture issue in the fuel or something more?