[mtucker666]

Make sure you insert the challenger car with the guide fully to one side which I've no doubt you are doing. However I can sympathise - the first challenger I had worked intermitently and then after a few hours of trying to get it to work all it would do is shoot off a full power. I could not get it to work. The retailer happily swapped it and I've had no problems whatsoever with my current one.

If you can't find an answer I'd return it.

Matt