the ground wire running from the starter solinoid to the starter sounds to be bad
You can turn the key to the "run" position, and jump across the solenoid with a screwdriver or something metal. If the starter turns, you have a bad solenoid.
Could be a faulty ground wire. Not very rare to happen
Either your starter solenoid, if not check the neutral safety or clutch safety switch.
You Should Buy The Starter Pack Because You Will Have All The accessories
If the starter has a direct ground short, it is possible that many electrical accessories/electrical components will act like they have hardly any power or not come on at all. Fastest way to find out, by jumping the two big screws on the selinoid. (You do this by placing a screwdriver across the two bolts) The vehicle will do nothing and the starter will have some sparking to it, only if the starter or celiniod is bad. If it is good, it will attempt to start.
I would say you have broken teeth on it, or your battery may be getting too low, while your key is in the ignition in the on position, take a screwdriver and touch the B+ wire on the starter solenoid ( may take a few tries but should start)! I would also advise that you get it replaced!
starter solenoid sticking
Bolt the starter into the starter position. There will be three starter retaining bolts. Connect the cables to the front of the starter.
its free when you buy the starter kits.
Place the starter into the starter position and secure it with the starter retaining bolts. Connect the starter cables to the front of the starter.
You cant really, sometimes shadetree mechanics can get a few extra weeks out of a starter that has a bad solenoid by hitting the starter with something. After a while that wont work either. You can use a screwdriver to cross connect the two large terminals on the starter to bypass the solenoid but its not good to do and also dangerous. If you have some kind of ignition problem that you cannot figure out but still need to operate the car in emergencies or to keep from losing a job you can buy a remote starter switch from an auto parts store ( about $10 ) and connect the alligator clips to the 2 large terminals on the starter, then with the ignition switch in the run position press the button to start. Tuck the switch away under the hood for the next start.
Sounds like a bad starter solenoid