Carpool Karaoke almost didn't happen when guest Mariah Carey refused to sing

James Corden recalled in an interview that Mariah Carey refused to sing for the feature in which he invites celebrities to belt out their hits in his car. "We’ll just drive around and have a chat," she insisted.  Indeed in the final cut of the viral hit Mariah tells James: 'I’m not singing today, I was up all night. but she eventually joins in with the sing-along as the British host blasts her hits