Water leaking into my transmission of my Honda accord
Most probably from the transmission cooler. It's usually part of the radiator. If in fact that is what has happened, You will need to replace the radiator, flush the cooling lines, and flush the transmission as well.
Tom has nailed it, only way water can get into the tranny unless directly put into it thru the filler. The cores inside your radiator that separates the transmission cooler tank (built into the radiator) have rotted and allowed the water to leak into the tranny and also the other way when sitting.
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