[Excaliber]

G.R. touched on this with his post.

None of the four terminals in question are "ground". Only the metal case of the solenoid is to be grounded. On many applications only ONE of the small terminals is used, the S terminal to make the solenoid "turn on". The other small terminal is entirely optional depending on the type of ignition system you have.

Again, NO terminals on the solenoid are to be grounded in ANY way.