Ibrar Shah was so angry with the way Esta Joy struggled through snow and slush that he pulled a knife on her passenger when she stopped, Wolverhampton Crown Court heard.
The furious 50-year-old followed the car onto the forecourt of a garage on Tettenhall Road, Wolverhampton, on December 11 last year, said Mr Ekwall Tiwana, prosecuting.
Miss Joy had given a lift to Willard Barrett and intended to drop him off at the filling station but when the passenger door opened the defendant put the point of an eight-inch blade to his throat, the court was told.
The woman motorist managed to drive off with her passenger still in the car and neither suffered any physical injury.
Shah was arrested soon afterwards but the knife was never found.
Mr Simon Williams, defending, declared: “It was something completely out of character.
"His last conviction was nine years earlier and he had no previous conviction involving violence.
"It must have been a horrible experience for the complainants but neither was injured.”
Mr Barrett said in a victim impact statement read to the court that the incident was so traumatic he had to take three months off work.
He suffered flash backs and could not sleep well. The driver said she had never felt so frightened before.
Shah from Upper Street, Tettenhall, was found guilty of possession of the knife after a trial and had been remanded for pre-sentence reports.
He was sent to prison by Recorder Nicholas Bacon QC who told him: “It was an extraordinarily dangerous thing to do. The psychological effects of your actions were considerable.”