In the "Map Controllers" panel, make sure to select "Mode 1" and do not check the option to automatically switch modes. If you do and do not have "Mode 2" mapped, vehicles will not work.
That said.
There are two columns in the "Map Controllers" panel which show the input name from the joystick (provided by the joystick) and the command associated with that input.
Under the first column, each axis will also have a set of numbers in parantheses. All these axises have a range from 0 to 65535. Check each one by moving the stick to its extremes for each axis. If the numbers appear to be normal. Make sure there is a command directly across the row from the input.
Pressing "Default Map" should have caused the game to fill in the things it knows about with some standard commands, such as the X and Y axis. Once that is done, the only thin that would prevent the axises from working is if the stick is not calibrated in Windows and the game.
Hope that helps.