Got a 2002 Ford Expedition
turn the key and hear a clicking like cylinoid. battery has a full charge, my
alternator good. Could this be a ground issue.
The starter solenoid will click if it is not getting enough battery voltage to hold it closed (hold down voltage). Make sure all connections are tight, and cables are good, and battery contacts are clean and tight. After a while the starter solenoid does wear out and may need to be replaced. Hopefully this will get you started.
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