Federal safety regulators are investigating Tesla’s Model Y SUV after at least two instances in which owners said their steering wheels became detached while the vehicle was being driven. The National Highway Traffic Safety Administration is looking at the 2023 model year. It said in the two instances in which the steering wheel came off, the cars were delivered to buyers without the retaining bolt that attaches the steering wheel to the steering column. The report from the agency did not say if there were accidents or injuries as a result of the problem. NHTSA said around 120,000 vehicles on US roads could be affected by the problem. This is an investigation, a step the agency takes before ordering a recall. Tesla is not the only company facing safety questions about its steering wheel. Nissan also just disclosed to NHTSA that it is recalling about 1,100 Nissan Ariyas, its electric SUV, because it may be missing a bolt required on its steering wheel. There were three vehicles found in dealer inventories in which there was too much play in the steering wheels, and upon inspection it was discovered the bolts were missing in each. But in none of those cases did the steering wheel come off while the cars were being driven, and there were no reports of accidents or injuries caused by the missing bolts. In February, Tesla was required to issue a recall of nearly 363,000 vehicles equipped with what it calls its “Full Self Driving” software after NHTSA determined it “led to an unreasonable risk to motor vehicle safety based on insufficient adherence to traffic safety laws.” Among the traffic rules the cars violated in FSD mode was “traveling straight through an intersection while in a turn-only lane, entering a stop sign-controlled intersection without coming to a complete stop, or proceeding into an intersection during a steady yellow traffic signal without due caution.” Tesla CEO Elon Musk objected to calling that a “recall,” saying it entailed only an over-the-air software update that did not require the owner to bring the cars to service centers to be fixed. But Tesla did order a recall last month of 3,470 2022-2023 Model Y cars due to bolts in the second-row seat back frames not being secured correctly, which could cause the seat belts in those seats to not work properly in a crash. Tesla has not had a public relations staff for several years and email inquiries to its press office are no longer accepted. CNN’s Ramishah Maruf contributed to this report.