When I start my car I'm getting a spark at the connection between the negative battery cable and the chassis. I removed the bolt and tried to clean it up some as it's a bit rusty and also the connector on the end of the cable. Still it sparks.

What might cause that?

 

Did you try sanding down the part where the ground wire meets the chassis?

 

Not on the chassis itself. I just used a battery terminal cleaner on the bolt and the wire loop connector. I'll have to try sanding on the chassis. Or maybe just brush it with the terminal cleaner too.