I was riding my 2009 street glide when the odometer started going up and down then the check engine light came on and off,when I came to a stop the idle dropped to 500,then it went back to 1000 rpm,any ideas whats wrong.

 

Did you check for trouble codes?

edit first thing I would check is the connector at the throttle body I would clean it with contact cleaner, check for fretting then use a little dab of Dielectric grease on it.

 

I would guess that you mean the speedometer needle went up and down since the odometer is a fixed display of miles traveled.
It is reading like the positive or negative cable at battery might be loose.
No mention of mileage but the speed sensor might be dirty, but it should not trigger a check engine light.
No mention of reading codes so i would guess that has not been done.