You've obviously missed a huge portion of the thread.
The green wire is likely shorted to chassis ground caused by poor routing by the previous owner. Is it really that tough to understand?
The unhooked engine ground has zero to do with anything. It should be hooked up, but won't change a single thing about it, and has nothing to do with any of the other parts changes/additions.
Box stock, these cars are garbage - wouldn't want to drive a stock one around the block, let alone to get ice cream.
