Balloon Powered Car Problems

For Science class we are required to make a car powered from either a balloon, mousetrap, or rubberband. I chose balloon. So I went on youtube to figure out how to make it and I used an empty water bottle as the base. For the axels I used Skewers with straws ove them and for the wheels I used water bottle caps. I cute a hole into the top to put the balloon attatched to the straw. In the video on youtube it worked perfectly, but mine wouldnt even move. What's wrong? Please help :D

With cars it all boils down to friction; that is to much resistance. Could be from the axles, could be just to heavy for the balloon force to push.
How hard is it to get the car to roll by just tapping it with your finger. If it isn't very very easy; then I wouldn't expect the balloon to do it either.
Might want to try different wheels.

I should think Lex Lodge has got a very good point here ~~~
It could be the wheels.....

If U reall followed EXACTLY to what was in that Y-T vid...
It shouldn't be a problem....:)

CHEERS & Nice DAy:)