Concerns are mounting over Kia’s earlier recall of more than 137,000 Seltos and Soul models, as the NHTSA’s Office of Defects Investigation (ODI) now questions whether the fix is actually working.

Kia has recalled 250,547 sedans for a rather concerning issue that could result in a melting, leaking gas tank, creating a fire risk. The issue relates specifically to the K5 midsize sedan, one of the ...