Okay, so I'm guessing the gear for my speedo is worn out or something. But why is it bouncing while I'm just sitting still and Idling? What would be making the gear or something else move?

 

Check the connection of the wires to the vss. Clean it up and put some dielectric grease on it see if that helps.

 

One's , got it.

 

Okay. I did unplug the wire a while ago and just cleaned it with a rag and it fixed it for a few miles so I will clean it right this time. Actually I just twisted the unit around because the sending wire unit was hanging loose so I did that to tighten the wire and drove it for 20 min and it seemed to fix it for now. But cleaning the connection is next. it was just driving me nuts!