Safety advocates have identified hundreds of complaints involving the 2011-2014 Sorento, Optima, Sonata and Santa Fe.
The Center for Auto Safety has petitioned the National Highway Traffic Safety Administration to investigate complaints of fires involving the 2011-2014 Kia Sorento, Kia Optima, Hyundai Sonata and Hyundai Santa Fe.
"There have been more than 100 consumer complaints of non-collision fires submitted to NHTSA regarding these vehicles and 200 complaints of melted wires in the engine bay, smoke, and burning odors," CAS says.
The group speculates the issues may be related to a supplier issue or manufacturing flaws at Kia's Georgia factory or Hyundai's Alabama plant.
Fires are not unheard of across the broader population of vehicles on the road, but CAS argues the 2.2 million vehicles highlighted in the petition have a much higher complaint rate than other similar vehicles manufactured during the same time.
"There is enough of a statistical disparity to suggest a systemic issue that NHTSA must investigate and seek a repair remedy as soon as possible," the group claims.