He died trying to stop a friend's car from being driven away.
Mr Zhu Beng Sheng, 68, tried to fight off the thieves, but was pushed out of the vehicle on Wednesday night.
The noodle seller died of severe head injuries in Johor Baru, The Star reported.
Mr Zhu was travelling in a car with a female friend on the way to her house in Taman Desa Cemerlang when they were involved in an accident.
The woman, who refused to be named, said that before the incident, the two of them had spent an enjoyable evening together.
She told The Star: "We were on the way back to my home and I was driving.
I realised that there was a car tailgating us and before I could do anything, there was a bang.
"We stopped and (got) out of the car to discuss with the (other) driver."
But four men got out of the other car and started shouting at them, insisting that it was her fault, she claimed.
As they were arguing over the matter, she noticed two of the men walking towards her car. They began to drive off in it.
Mr Zhu rushed to the car's front passenger seat and was seen struggling with one of the suspects in the moving vehicle.
"Within seconds, he was pushed out of the car and onto the road while the suspects sped off in my car," she said.
"I rushed to him, but he was already lying there unconscious." She said a passer-by rushed Mr Zhu to Hospital Sultan Ismail, where he slipped into a coma and died seven hours later.
Mr Zhu's son, Mr Liang Hui, 45, said he was not surprised that his father had reacted that way to fight off the thieves.
He said: "He always stood up for what he believed was right."
Seri Alam Superintendent Roslan Zainuddin said that the police had not arrested anyone yet.
Get The New Paper for more stories.