Originally Posted by :exnbp:
Get a voltmeter and test out how much voltage the battery is putting out. If it is above 10.45v it is a good enough battery to start the car. If not might try checking to see how much voltage the starter is putting out. Check ground wires from the battery as well

That 10.45v rule they teach you is so stupid. There's varying amounts of voltage/amps needed to crank different engines.
But for a 4-cylinder it probably applies

h: