There is still no sign of a missing teenager who fled from a high-speed car chase in rural South Australia almost two weeks ago.

Police and SES crews spent Saturday scouring isolated scrubland for 19-year-old Scott Redman, but did not find him.

Mr Redman was an occupant of a car involved in a pursuit on the Eyre Highway near Kimba on April 21, police believe.

The pursuit was terminated due to safety concerns, with the black station wagon found on a dirt road 40km east of Kimba four days later.

Efforts to track down the teenager have proved fruitless and police now hold grave fears for his welfare.

The land and air search is not expected to continue on Sunday, but police are still hopeful Mr Redman will be found alive and say they will continue to explore all lines of inquiry.

"The area in which we have been searching in is rural and isolated," Inspector Mark Hubbard said.

"It is possible that Mr Redman has also caught a lift with someone, but we have no evidence of that at this time.

"Mr Redman's family, friends and acquaintances have not heard from him, and we are appealing for him to make contact with authorities."

The car's other occupant was arrested in Whyalla on April 23 after hitchhiking to the town.

Mr Redman is described as 178cm tall, with a slim build and blonde hair.