The Spaniard was dropped by Citroen in favour of Sebastien Ogier at the end of 2010, but returns in 2013 to start his fifth full season with the Versailles-based team.
Sordo spent the intervening years with the Prodrive WRC Team, where he took two second places in a Mini John Cooper Works WRC.
"When I was at Citroen the first time, I was in the car all of the time," said Sordo. "Then when I was with Prodrive I wasn't competing all the rallies and not testing all of the time.
"Maybe doing something all of the time isn't such a goof thing, you get fed up with it, but then when it's not there you want it like crazy.
"Now, when I come back, I want it [success] more than ever."
Sordo is adamant his competitive instinct hasn't dimmed, either - especially after signing off by setting more fastest times than anybody on the Catalunya Rally last month.
"I'm more hungry to win that I have ever been," he said. "And the driving is as good as ever.
"The only small problem could be in places like Mexico. I didn't go there last year and now half of the rally will be completely new for me."
Sordo's original deal with Citroen was for 11 of the 13 rallies, with the for Junior World Rally Champion expected to miss Sweden and France.
Team principal Yves Matton is working to ensure Mikko Hirvonen's team-mate will be at the start line of every 2013 WRC round.