A 45-year-old man was clinging to life early Sunday after he was viciously stabbed in a road rage attack on the Upper East Side Saturday night, cops said.

The attacker got out of his car on East 61st Street near York Avenue at about 11:20 p.m. and repeatedly stabbed the victim — who was still in his car — in the torso.

Despite his severe injuries, the victim decided to keep driving, making it all the way to East 76th Street and Madison Avenue before he crashed into a parked car.

The victim was taken to New York Presbyterian-Weill Cornell Hospital in critical condition.

The attacker, who cops say is a black man with dreadlocks, fled in his blue Ford with Rhode Island plates.

Cops did not immediately know what the drivers had been arguing about.