[jQuery] auto submit

[finord]

Hello, I have a problem when sending data with jQuery, if sent by
clicking "Submit" if it works, but when trying to send it directly
when the input 'name' has two values, does not run with ajax, but it
does as a normal consultation.

Here you put the code on the form and the ajax, ajax is not much of,
and the script I did to my paritr some light on the web page and
jQuery, if I can say is wrong or could do

html code:
<form method="post" action="<?=base_url()?>add/APTV" id="fo3"
name="fo3" >
          <div class="contentA">
                <div class="row">
                        <div class="left">First name</div>
                        <div class="right"><input name="prod" class="text" 
type="text"
onkeyup ="if(this.value.length==2) submit()"><input type="text"
name="cta" id="cta" class="input-text"> <br></div>
                        <div class="clear"></div>
                </div>



<input type="hidden" name="op_key" value="1" />

<input type="submit"   name="mysubmit" class="green"/>

---------

js code:
$(document).ready(function() {

        $().ajaxStart(function() {
                $('#loading').show();
                $('#result').hide();
        }).ajaxStop(function() {
                $('#loading').hide();
                $('#result').fadeIn('slow');
        });

        $('#form, #fat, #fo3').submit(function() {
                $.ajax({
                        type: 'POST',
                        url: $(this).attr('action'),
                        data: $(this).serialize(),
                        success: function(data) {
                                $('#result').html(data);

                        }
                })

                return false;
        });

Thanks