It happened around 1 a.m. near Gulf Bank.
The man was northbound on the freeway when the good Samaritan spotted flames coming from the car and flashed their lights to get his attention, according to the Houston Fire Department.
The driver was able to exit the freeway and pull into a parking lot just as flames spread to the interior of the vehicle, HFD officials said.
There was no immediate word on the cause.
Vehicle fires caused an estimated $1.9 million in property damage in figures from 2018, according to the National Fire Protection Association.
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