My car starts when the key in the On position, but it should only start in Start position.
The most likely cause of this issue is a faulty ignition switch or lock cylinder. One of the tumblers may have fallen out of place causing a connection to the starter when there should not be. My best recommendation would be to have your ignition switch tested for faults by a qualified technician. If the switch requires replacement, a new key will also come with the switch and that will be your new ignition key. I would only recommend having the ignition switch replaced by a professional, as accidental cranking of the starter during replacement of the ignition switch could hurt someone.
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