Police have again been searching for the mystery object that killed Rutger Hale as he drove between Lake Hawea and Wanaka last year.
Mr Hale was killed on October 24 when the object crashed through the windscreen of his car and struck him in the head.
Police on Saturday combed an area near where the crash happened but Detective Sergeant Brian Cameron said "nothing of significance was found."
"Police regularly review information held in cases such as this to ensure that as much as possible, all avenues have been explored," Mr Cameron said.
The death of Mr Hale, who was 22, is before the coroner.
His girlfriend Danielle Oylear was in the car with him at the time of the accident, and was forced to grab the steering wheel and lift his foot off the accelerator to bring the car to a stop.
Analysis of parts of the vehicle in February revealed the object was made of, or contained, fragments of stainless steel of a common grade used in vehicle parts and other everyday items such as tools and cookware, police said.
The object also comprised common minerals naturally occurring in soil or dirt in the South Island.
In February, Detective Senior Sergeant Malcolm Inglis said the case remained open and if any new information came to hand it would be investigated further.
"Our thoughts are with the family and friends of Rutger Hale as we are at this stage unfortunately unable to progress the case to any satisfactory conclusion."