Ricky Burlton, 20, from Enfield, London, died after he was hit by a car on the A10 exit slip road at Hoddesdon, Hertfordshire.
Officers want to question Alexi Shyti, who is thought to have been living under an assumed named at the time.
Mr Shyti, believed to have been driving a Rover involved in the crash, fled the country the next day.
Albania national Mr Shyti sustained serious facial injuries in the crash on 4 June 2010, and was at Chase Farm Hospital in Enfield when police found him.
It is believed Mr Shyti - who told police he was Greek man Georgios Tsoulos - was living in the UK illegally with a fake EU passport.
Det Insp Pushpa Guild urged anyone with information on Mr Shyti's whereabouts to contact police.
"We know Aleksi Shyti had been in Albania and would also ask anyone with connections there and who knows where he may be to call us.
"We believe he may have now travelled to Greece and he also has connections to Italy.
"In the UK, he had connections in Hertfordshire, North London and Loughborough in Leicestershire."
Ricky's mother Dawn said: "Five years is an extremely long time not knowing what truly happened to our precious son and brother.
"However, the one thing Ricky's mother, brothers and sister have is our unity as Ricky's family to continue with our search to find Aleksi Shyti."
A fresh appeal has been made in a bid to find a man wanted in connection with a fatal crash five years ago.