Folan scored twice for The Tigers either side of a Tommy Smith goal but late goals from Jamie O'Hara and Kanu gave Portsmouth a 3-2 home victory.
In the Championship, Coventry City dropped down to 11th in the table, thanks to Middlesbrough, Doncaster and Blackpool all getting draws.
There were wins for Scunthorpe, Ipswich, West Brom and Nottingham Forest who beat bottom side Peterborough whilst in the evening game, managerless Bristol City drew 2-2 with Newcastle.
Norwich who drew 1-1 at Swindon lead League One by eight points.
Former City winger Liam Davis scored for Northampton in a 2-0 win against Morecambe. Gary Breen scored an own goal in Barnet's 2-1 win at Darlington.