Go with the Clouds, North-By-Northwest Vol. 3 (manga)

From Aki Irie the creator of 'Ran and the Gray World".

Kei Miyama lives in Iceland and has 3 secrets: he can talk to cars, his weakness is beautiful girls, and he works as a detective.
After a much-needed vacation, Kei returns to the beat--a boy has gone missing, and his family is desperate to find him. A girl named Sigrún leads him to a mysterious flophouse, and Kei uses his strange affinity with technology to crack the case, this time by communing with cell phones as well as cars. But he has a strange feeling he's visited the apartment before, and tension builds to violence as seemingly unrelated mysteries begin to converge...