Random Random Random Timer... Problems

Heyy guys. I know you guys know this stuff backwards & forwards so maybe you can help.

This is a 2 part problem. Part 1 is Im trying to create a timer that functions at random intervals, the function in this case is playing a MC of a car driving on a freeway in 1 to 10 second intervals to give the feeling of, well, randomness. (I’ve attatched the .fla file if that’ll help).

So it works, but not quite as it will generate intervals only twice before it repeats the second interval over and over. So the car will ‘drive’ in say, 7 seconds the first time and then it will drive in 3 seconds, then again in 3, and in 3 and in 3 seconds. Ive tested it so much I know its not coinsidence.

Here’s the code Im using (located in the freeway MC):

[COLOR=red]var interval:Number = random(10)+1;
function someCodeToRun() {
_root.freeway.diffcars.drive01.gotoAndPlay(2);
}
setInterval(this, “someCodeToRun”, interval*1000);[/COLOR]

Part 2 is I also wanted the cars to be different colors, which is why there is a diffcars MC with different frames of cars, but now Im not even sure I was headed in the right direction with that.

Ultimately Id love to have different colored cars driving on the freeway at different intervals. Can anyone figure this out?