Two men got out - one of them a stocky, caucasian man in his 30s with most of his top teeth missing, who approached asking for a lighter.
The other was a Maori man in his mid 20s, of skinny, athletic build.
"I handed over my lighter but noticed something a bit dodgy and told him he could keep it.
"By that time, he ran at me with a sharpened screwdriver. I didn't even have time to turn on the car.
"He told me that he would poke me in the eyes. I hadn't unlocked the doors, and when I did a Maori guy got into the passenger side and started jabbing me in the back while the other guy pulled me out of the car door."
Without any cellphone to call for help there was nothing to do but watch helplessly as the car and papers required to gain his engineering qualification sped off towards Clive, followed closely by the Pajero.
A shaken Mr Ellis-Jones climbed up to the roadside and flagged down a couple who were holidaying in Hawke's Bay.
They took him to Clive police station, which was unmanned, before dropping him at home, from where he called police.
Senior Sergeant Fred Van Duuren was not aware of any other recent carjacking incidents in Hawke's Bay, adding that such events were random and usually unplanned.
"In that type of situation, the best thing to do is to comply and try as best you can to really focus on details of the offenders, vehicles, etc," he said.
Police were following positive lines of inquiry using the descriptions they had of the offenders and hoped to reunite Mr Ellis-Jones with his precious paperwork.
"It's obviously a priority for us to stamp out this kind of offending. The staff will be diligent with any information we receive.
"We are following some leads," Mr Van Duuren said.
Without the folders containing his papers and process sketches, Mr Ellis-Jones would need to redo all the work before November, when he is due to finish his apprenticeship.
All the papers had his name on them and were inside a blue nailgun bag, in a blue folder.
-Anyone with information on the incident can call Crimestoppers anonymously on 0800 555 111.