I had just replaced the battery in my 2016 Ford Focus. The old battery was dying, but would start immediately until it could not start anymore without a jump. Ever since replacing the old battery with the new battery two days ago, I have had a sluggish start with it almost all the time.
The old battery had habitual corrosion buildup on it's positive post. The auto tech who installed the new battery, he cleaned out the battery compartment. He cleaned the positive terminal and what he could see of any corrosion on the positive cable near the positive terminal with neutralizing spray. So, now that all this has been done for this new battery, the car now has this sluggish start.
What could be happening? Thank you so much for your time and attention to my concerns! :-)
My car has 37391 miles.
My car has an automatic transmission.
Since you have effectively eliminated the battery as a potential issue, I would suggest having the alternator checked to determine if it is receiving the proper amount of voltage from something called the voltage regulator. The voltage regulator regulates the charging voltage that the alternator produces, keeping it between 13.5 and 14.5 volts to protect the electrical components throughout the vehicle. The voltage regulator controls the field current applied to the spinning rotor inside the alternator. When there is no current applied to the field, there is no voltage produced from the alternator. When voltage drops below 13.5 volts, the regulator will apply current to the field and the alternator will start charging. When the voltage exceeds 14.5 volts, the regulator will stop supplying voltage to the field and the alternator will stop charging. This is how voltage output from the alternator is regulated. When the voltage regulator is not working properly, this may cause the alternator to allow the power the alternator supplies to drop resulting in the battery dying again. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.
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