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Q: Ford KA battery light on, replaced but stilll on. Car Idles very low and cuts out if not driving.

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Ford KA battery replaced, light still on, idleing low and will cut out without sufficient revs. Oxygen sensor gone since December as mechanic MOT'd without fixing! I understand this can cause worse problems should other sensors go. Could not afford to take to another mechanic, car is now risky to start in a morning as needs revs for engine to start up. I want to know if this will be an expensive fix/likely to happen again/ worth the cost? Many thanks.

My car has 78000 miles.
My car has a manual transmission.

Hello, thank you for writing in. From the sound of it, you may be having an issue with the charging system. You will want to have the alternator inspected. There are tests that can be done while on the vehicle with a voltmeter, or there are bench tests that can be done at most automotive parts stores. With that being said, you will also want to look at the battery cables and ground connection. Make sure all of these are clean, dry, and tight. The alternator powers the vehicle once the battery is started. It is charged by the drive belt which speeds up with engine speed. This would explain why you are having better luck while increasing the RPMs. For more help replacing the alternator, contact our service department to schedule an appointment.

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