US regulators probe over 137,000 Kia vehicles after complaints of ineffective recall remedy

US regulators on Friday opened an investigation into more than 137,000 Kia vehicles to evaluate how effective a recall remedy was for defective oil piston rings.

Kia in February launched a recall of 137,256 vehicles, including 2021-2023 Seltos and Soul models, over concerns the piston oil rings might have been incorrectly manufactured.

Defective piston oil rings could damage the engine over time and increase the risk of a fire.

In April, the carmaker made available a recall remedy that included inspecting the vehicle to see whether an engine replacement was necessary. 

But the National Highway Traffic Safety Administration said it reviewed 47 complaints that alleged the recall remedy was ineffective or unavailable. 

The audit will investigate Kia’s remedy measures as flagged in the complaints, which were received between April to June of this year.