This happened few weeks ago, where starter would turn slower by the day, until would not start, or turn over engine. Tried to charge battery, and then replaced it. Did not help, so replaced batter terminals. No help, so removed starter and had it tested at auto parts store. Really expected it to show bad, but it did not. I don't know if there test really shows the strength of the starter, actually under a load. Anyway put the same starter back, and it worked well for a few weeks. Over the last few days, starter turning slower, and finally today, would not start. Batter shows 12..5 volts so thinking it is good.
Thinking maybe the starter is really failing, but wanted to be a little more assured before replacing it.
My car has 55000 miles.
My car has an automatic transmission.
Hello. It sounds like you have bad positive battery cable. When the cable fails it creates a lot of internal resistance that will cause this. I would usually do a voltage drop test of positive cable to verify this. It can also be an internal engine issue causing high drag so I would try moving the engine my hand. If it is really hard to turn then there is an engine issue. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to you to [diagnose why it is not cranking] https://www.yourmechanic.com/services/car-is-not-starting-inspection
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