Mr Rowe said there was no reason to believe speed or alcohol were factors in the crash and that the truck driver and passenger - a father and son from Hastings - did all they could to prevent the accident.
"At the moment we are just going from what we have got from the scene and pulling together from that, and hoping like hell that a miracle happens and the young boy survives to tell us himself.
"We don't know if there was anything in the car to distract him, but alcohol and speed don't appear to be involved, all we know is he was travelling from home.
"We are waiting to speak to his mum and dad because as you can imagine they have a lot more on their plates right now. We need to know more background about where he has been and anything that is relevant to the investigation."
The collision happened when the young man's car took a sweeping left-hand bend.
"The driver and passenger of the truck, they're very shaken but have very minor injuries.
"The truck driver isn't at fault, he did everything he could."
The truck was carrying the men's work tools.
Emergency services were at the scene until about 1pm on Saturday, and road blocks at either end of Stock Rd diverted traffic.
The man was originally taken to Hawke's Bay Hospital by St John Ambulance, before being transferred to Wellington.
Two 19-year-old females were taken to the Hawke's Bay Hospital at lunchtime yesterday after a collision outside the Waipukurau Golf Club on SH2, Central Hawkes Bay.
St John Hawke's Bay district operations manager Stephen Smith said one of the young women had minor chest injuries, and the other had minor abdominal injuries.
