Speedometer problems

I have been trying to fix the speedometer on my 1991 240sx for awile now. It just wont work! it's really not a big deal but it still makes me mad....any one have any ideas on how to fix it?



Cop- son do you know how fast you where going?
Me- well....no i dont how fast was i going?

is it an analog or digital? Might want to check the speed sensor or maybe the gauge itself.