West Midlands Fire Service believed the blaze was 'accidental'.
Firefighters were called to Essington Road, Willenhall, at 12.01am today.
Twitter user @tarcief wrote online: "Car fire exploded...fire service soon sorted it."
A West Midlands Fire Service spokesman said: "A car was well alight on a public roadway.
"It is not believed to have been started deliberately.
"We used one hose reel jet to put the fire out.
"Two of our firefighters were wearing breathing apparatus."
The spokesman added that it is believed the car was being used when the blaze took place.
However it is unclear if there was any injuries.