Problems loading UIWebView

I'm attempting to write a SplitView control program in which pressing a table cell in the masterViewController causes an associated web page to load in the detail view controller. I have the following method in the detail view controller that I can confirm is getting called and is receiving the correct input:

  -(void)masterAction:(id)sender  {

    NSString *http = @"http://";
    http = [http stringByAppendingString:sender];
    _urlString = http;


    NSURL *url= [NSURL URLWithString:_urlString];
    [self.web loadRequest:[NSURLRequest requestWithURL:url]];

     }

However, nothing is loading. Any ideas why this might be? The only way I've been able to get anything at all to load is to insert something similar to the following in my viewDidLoad method:

NSURL *url= [NSURL URLWithString:@"http://www.google.com];
[self.web loadRequest:[NSURLRequest requestWithURL:url]];

The method is being called using:

-(void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSDictionary *thread = [self.issueData objectForKey:@"responseData"];
    NSDictionary *feed = [thread objectForKey:@"feed"];


    NSArray *entries = [feed objectForKey:@"entries"];
    NSDictionary *posts = entries[indexPath.row];

    NSString *urlString = [posts objectForKey:@"link"];
    NSArray *split = [urlString componentsSeparatedByString:@"url=http://"];

    NSString   *url = [split objectAtIndex:1];

    [self.delegate masterAction:url];

}

set the delegate of webview.

and try this.

NSString *myUrl = @"http://www.YourWebSite.com";
NSURL *webUrl = [NSURL URLWithString:myUrl];
[webObj loadRequest:[NSURLRequest requestWithURL:webUrl]];