The story was written some time before 2008. It's about a male cop or detective and is set in a cityscape in an alternate world set in the future. The scenes that stand out to me is that he had a sentient car or bike. Lived high in a skyscaper type building. There where some large cats that traversed through the city and normally met him on his roof. And the energy source ran on the dead of the city, transported to large factories or reactors.
Sounds like the Tristopolis series by John Meaney. There are 2 books in the series; Bone Song and Black Blood. The main character is a cop named Donal Riordan. In the second book, he inherits a car, that is an embodied spirit. He lives in the penthouse of a tall building. There is scene with him communicating with a number of cats at the top of the building to help him search for someone. The city is powered by the bones of the dead, stored in underground "reactors."Also, one of the other cops in his task force, has a sentient motorcycle.