Hola, ya lo arregle:
<script>
function window.onbeforeprint(){
noImprimir.style.visibility = 'hidden';
noImprimir.style.position = 'absolute';
noImprimir1.style.visibility = 'hidden';
noImprimir1.style.position = 'absolute';
}
function window.onafterprint(){
noImprimir.style.visibility = 'visible';
noImprimir.style.position = 'relative';
noImprimir1.style.visibility = 'visible';
noImprimir1.style.position = 'relative';
}</script>
<p id="noImprimir">Texto no imprimible</p>
<p id="noImprimir1">Texto no imprimible</p>
El problema era cuando se lo ponia a mas de un objeto, asi que lo modifique y anda.
Si empieza a fallar les aviso, salu2