2005 kia optima won't crank
Did you replace the fuel pump relay at the same time? Next check for battery voltage at the fuel pump connector when you first turn on the key, it will only last a few seconds and then shut off, if you have that great then check the ground wire make sure it is clean and tight, if you have both of those and the pump still won't run then you have a bad new pump or messed something up during the install.
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