A teenager who seriously injured a motorists when he crashed a stolen car in Canberra's south has pleaded guilty to negligent driving.

Joshua Luke Winters also pleaded guilty in the ACT Magistrates Court on Friday to charges of unlicensed driving and failing to give assistance after an accident.

The court heard the 19-year-old was on deferred sentence for other driving matters when he caused the crash while driving a stolen car and then fled the scene before handing himself in to police.

Winters, of Kambah, had been driving a stolen blue Ford Territory and had been turning out of Livingstone Avenue when he struck a black Holden Commodore on Sulwood Drive.

The engine block of the Commodore caught fire and the driver was briefly trapped before members of the public and emergency services pulled him clear.

The 34-year-old victim suffered injuries to his head, chest and legs.

Winters ran off after the crash, escaping into the nearby Mount Taylor Nature Reserve where a police sniffer dog team and the Rural Patrol in a four-wheel drive gave chase.

He handed himself in to police later that day.

Magistrate Peter Morrison ordered an updated pre-sentence report.

Winters will remain in custody until he reappears in March.