Bill, is the car new or used?...reason I ask is that someone may have had it apart and put the wrong wheel set on the p/u truck. You'll see the hall effect sensor on the one truck for sensing the chuff- which is set about by the one axle that has a magnet in the wheel. Take a small screw driver and put it by that wheel to see if it's attracted by the magnet...if not check the other wheels for magnetism and install the one where it would need to be.
If the wheel checks out ok, then it's something on/in the board.... I've got the green RI livery steam sound version.
Dang...looking at the time I'm not gonna make it to wheaton today....oh well, next month I guess....I hate going late even if they are supposed to be open till 3pm.