related_query.php

<?php

// Grab all the spare_parts
$spare_parts = get_posts( array( 'post_type' => 'spare_parts' ) );

// Loop through the spare_parts
foreach( $spare_parts as $spare_part ) {
	// Save their meta values
	$related_meta[] = get_post_custom( $spare_part->ID );
}

// Loop the values
/*
foreach( $related_meta as $related_product ) {
	
}
*/

$args = array(
	'post_type' => array( 'products' ),
	'p' => $related_meta
);

$related_products = query_posts( $args );

while( etc ) : 

endwhile;

?>

have_posts()) : while ($spare_parts->have_posts()) : $spare_part->the_post(); //Grab the spare_part meta and loop through the values foreach (get_post_custom( $post->ID ) as $meta_value) : //Grab the products with the same title as the meta value $related_products = new WP_Query("post_type=product&post_title=$meta_value"); if ($related_products->have_posts()) : while($related_products->have_posts()) : $related_products->the_post(); //Display a list of all products echo $post->post_title; endwhile; endif; endforeach ; endwhile; endif; //Set the default page query back to itself wp_reset_query(); ``` ?>