my is cranking without key I had to disconect the baterie when I connect it staring crank
This suggests you may have a faulty starter solenoid. The starter solenoid is located on the starter and has internal electrical contacts that transmit electricity to the starter. When this fails, it may cause a clicking sound and will not allow the starter to engage the flywheel when you turn the key. In other cases it may cause the solenoid to engage the starter intermittently or on its own as you have described. I would suggest having a professional from YourMechanic come to your home to diagnose your starter.
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