Some motorists managed to swerve around him but Manukau's vehicle knocked him 56m through the air.
It wasn't until Manukau arrived home and told his wife he had hit someone and may have killed them that he returned to the scene to search for the body. Unable to find anyone, he and his wife returned home and phoned the police.
Less than two hours after the crash, Manukau was breath-tested and returned a reading of 547 micrograms of alcohol per litre of breath.
Yesterday, the Tauranga District Court heard how Manukau told police: "Why put this on me if he's sick of living?"
Judge Peter Rollo took the teenager's actions into account but told Manukau that a third drink-driving conviction within three years was a "totally unacceptable situation".
"I emphasise again you were drinking all day and deliberately decided to drive home, taking your chances, [which] unfortunately caused a tragic outcome," Judge Rollo said.
"A young man has lost his life and albeit that he, to some extent, contributed to the outcome, it was your driving that killed him."
Judge Rollo said the lives of Mr Stevens' family had been "put on hold" as they struggled to deal with the loss.
Parents David and Miriama were too distraught to remain in Te Puke and quit their jobs and left for a new home in Taumarunui.
A tearful Mrs Stevens struggled to read a victim impact statement in court, saying she felt "deep sadness" and "huge guilt" over her son's death.
Mr Stevens said the death had "affected the family hugely" and had left them "hurt and angry". He said his 14-year-old daughter had lost a big brother she looked up to.