All my electronics are off but the car starts.
I had a battery drain when the car is parked, I would remove a terminal
whenever I park the car. Now the electronics have completely shut off but the
car runs when start the ignition. Please help. I suspect it's my alternator but
I'm not sure.
It has nothing to do with your alternator. Your alternator just charges your battery. You must have some short somewhere and that could be serious. You need to have the car inspected immediately, it could be only time before it could die on you completely or worst catch on fire. Take care of it immediately for your own safety.
Try this first/ https://www.youtube.com/watch?v=9wLrTjeb9TY
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