Federal safety regulators are looking into Tesla again — this time over concerns of steering wheels falling off 2023 Model Y vehicles.

The National Highway Traffic Safety Administration said Wednesday it received two complaints from owners of the 2023 Model Y that the steering wheel came off while the vehicles were being driven.

The investigation will assess the scope, frequency and manufacturing processes associated with this issue, the agency said. An estimated 121,089 Model Y vehicles are part of the investigation.

Both vehicles were delivered missing the retaining bolt, which attaches the steering wheel to the steering column, according to NHTSA. A friction fit was able to maintain the connection between the steering wheel and the column splines during operation of the vehicle — until of course, it didn’t.

Both vehicles received an “end of line” repair that required removing and re-installing the steering wheel, regulators said.

The 2023 Model Y has had four recalls, according to documents posted on NHTSA’s website. In November, a recall was issued for taillights that may fail to illuminate. A recall for suspension fasteners that were improperly tightened was issued in December; another one in February was for the second row seat frame possibly being improperly secured.

The fourth recall, issued in February, covers all Tesla vehicles with the upgraded Full Self-Driving software. Tesla issued a recall of its Full Self-Driving software after federal safety regulators said the advanced driver-assistance system could allow vehicles to act unsafe around intersections and cause crashes. FSD software does not actually drive on its own. A human driver is expected to be able to take control at any time.

The recall affects as many as 362,758 vehicles equipped with the software, according to the notice.

Tesla has since paused the rollout of its Full Self-Driving beta software in the United States and Canada until it can remedy the software issue.