how do I know if the problem with my starter or could it be my relay switch
It could be dirty contacts on the ignition switch. It could be the neutral safety switch. It could be the solenoid mounted on the starter motor. --- To see if it's the starter or something else, next time it doesn't turn over, hook your meter to the small wire on the starter solenoid. If you see 12 volts when the key is on "Start", your starter motor is bad. If you don't see 12 volts, it's one of the other parts of the system.
for the cost of a solinoid id replace it,you may have it working hearing the click with key on start ,but the discs inside may be burnt not contacting
The question asks how to diagnose what the problem is. That's one of the steps of root cause analysis. We see questions all the time where someone has replaced a half dozen items and the problem persists. --- I've been in a position where I replaced everything because of time or distance restraints and this problem is most likely with the starter but it has not been confirmed.
If you get a clicking noise, tap on the starter with a hammer, (don't try to hit a home run). Then try to start it. If it starts the starter is shot. Not really shot, the brushes probably require replacing, if you want to take the thing apart.
Remove the starter & hook 12 volts to the starter & it should turn over. Most important is to make sure all electrical connections are tight & grounded proper.Soloinod will be the problem 95% of the time if not a bad connection.
with my starter problem>>>> i changed the starter and tested the voltage but when i put my battery connectors.. it sounds like the starter is spinning before i even put the key in the ignition....
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