Twenty cars were damaged in Saturday's fire outside the grounds of the Big State Festival.
South Brazos County Fire Chief Emily Staples says the fire may have started when a driver attempted to free their vehicle after it became stuck in a hole in the north parking area of the Texas World Speedway.
The driver gunned their engine to get out and that may have sparked the dry grass.
Staples says fire crews were able to bring the fire under control after 30 minutes despite winds gusting at 20 MPH on Saturday.
Big State Festival officials are assisting those whose cars were damaged.