That's really hard to say with out looking at the .blend file to see what's going on. 

I think my first couple of guesses would be:

1.  If you have multiple cameras, make sure the one you want to use for rendering is set as the default camera  ( I believe it's CTRL-0 to set it as the default )

2.  Check the frame numbers in the Car's IPO, the Cameras IPOS and the numbers set for the animation to make sure they all coincide correctly.  IE - if the camera / animation is set to go from 500 - 1000, the car's IPO may be going from 0 - 500, in which case it may have animated itself off the screen by the time the camera starts rolling.

That's about all I can guess at with out looking at the file.  Screen shots help, but there's so many other factors to look at, sometimes it's just not enough.

Scott

Reddog9
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