Tags não exibem conteúdo do CPT

Bom dia.
Criei um custom post type para gerenciar portfólio, nele habilitei as tags para que eu possa categorizar os sites que já fiz.

No layout eu coloquei um widget de tags no rodapé, quando clico em alguma tag ele me retorna um resultado vazio, meu CPT está assim:

<?php
function theme_factory_portfolio() {
	$labels = array(
		'name'                => _x( 'portfolio', 'Post Type General Name', 'themefactory' ),
		'singular_name'       => _x( 'portfolio', 'Post Type Singular Name', 'themefactory' ),
		'menu_name'           => __( 'Portfolio', 'themefactory' ),
		'parent_item_colon'   => __( 'Parent:', 'themefactory' ),
		'all_items'           => __( 'All', 'themefactory' ),
		'view_item'           => __( 'View', 'themefactory' ),
		'add_new_item'        => __( 'Add New', 'themefactory' ),
		'add_new'             => __( 'New Portfolio', 'themefactory' ),
		'edit_item'           => __( 'Edit', 'themefactory' ),
		'update_item'         => __( 'Update', 'themefactory' ),
		'search_items'        => __( 'Search', 'themefactory' ),
		'not_found'           => __( 'Not Found', 'themefactory' ),
		'not_found_in_trash'  => __( 'No portfolios found in Trash', 'themefactory' ),
	);
	$rewrite = array(
		'slug'                => 'portfolio',
		'with_front'          => true,
		'pages'               => true,
		'feeds'               => true,
	);
	$args = array(
		'label'               => __( 'portfolio', 'themefactory' ),
		'description'         => __( 'Create a portfolio section in your site', 'themefactory' ),
		'labels'              => $labels,
		'supports'            => array( 'title', 'editor', 'excerpt', 'thumbnail', 'revisions', ),
		'taxonomies'          => array( 'post_tag' ),
		'hierarchical'        => false,
		'public'              => true,
		'show_ui'             => true,
		'show_in_menu'        => true,
		'show_in_nav_menus'   => true,
		'show_in_admin_bar'   => true,
		'menu_position'       => 30,
		'menu_icon'           => get_template_directory_uri().'/images/portfolio-icon.png',
		'can_export'          => true,
		'has_archive'         => true,
		'exclude_from_search' => false,
		'publicly_queryable'  => true,
		'query_var'           => 'portfolio_query',
		'rewrite'             => $rewrite,
		'capability_type'     => 'post',
	);
	register_post_type( 'portfolio', $args );

}
add_action( 'init', 'theme_factory_portfolio', 0 );
?>

No “query_var” alterei para true e mesmo assim não exibe nenhum conteúdo cadastrado neste CPT nas tags do meu site, o que pode ser?