Questionbattery is good/starter replaced/all wires checked. Battery stays charged. Can get it started with a boost from a alive vehicle but not a starter box or a vehicle that isnt running.... what could cause this??
AnswerYou have a vehicle that likely has a corroded cable or a bad ground connection. Something is causing a much higher than normal current requirement to start the engine.
Possibilities include:
1) Cables that have corrdoed or dirty ends.
2) Cables that have corroded under their insulation near their ends (cannot be seen without removing insulation).
3) A bad igntion switch. The contacts can go bad and sometimes jumping the vehicle from another one will overcome the bad contacts.
4) The "replaced" starter is defective. This happens occasionally with rebuilt starters.
5) A loose connection. It is hard to install a starter on GM vehicles because the wiring attaches to the top of them. Sometimes the connections will loosen as the starter is raised into position and bolted in.
6) Has the battery been load tested? A battery can seem fine, but have an internal problem which prevents it from delivering full current.
7) The side terminal connections on GM vehicles are marginal, at best. They will overheat and conduct less current than they should.
8) A missing, loose, or corroded ground connection. Check all grounds thoroughly.
Check the cable leading from the battery to the starter when cranking the engine. Does it get hot? If so, this indicates a much higher than normal current draw.
