Problem connecting Arduino

Hi, I’m having trouble connecting the Arduino Uno R3.

It all started when I started a 2.4v engine, but accidentally I ended up calling 3.3v (the information was bad to read), so I saw the engine did not turn up (I think), after that the Arduino is not recognized by the pc and the led ON turns on very fast and then it turns off and does not come back on (when it is connected to the usb) maybe I have turned the motor and thus creating a reverse current, I’m not sure.

I really appreciate the help.

A rather muddled explanation.

The Arduino is plugged into the PC. Nothing else connected. You try and upload the "blink" code. What happens?

The USB port may ave gone into protection mode because of to much current being pulled. try resetting the USB port and see if that helps.

Where did you connect the wires from the engine?