DETROIT — Owners of more than 300,000 Hondas have yet to get their air bags repaired, despite warnings from the automaker and regulators that the inflators have an extremely high chance of rupturing and causing injury or even death.

Last week authorities said one of those air bags, equipped with an inflator made by Takata Corp., ruptured and killed a California woman, adding urgency to the search for the noncompliant vehicles.

About 69 million Takata inflators have been recalled due to possible rupture. In June, government regulators said testing showed that inflators in 313,000 older Hondas and Acuras had as high as a 50 percent chance of rupturing in a crash. The regulators told owners of the cars to stop driving them and get them repaired. But four months later, only 13,000 of the cars have been repaired.

Takata uses ammonium nitrate to create an explosion to inflate air bags. But it can deteriorate when exposed to heat and humidity and blow apart a metal canister, spewing shrapnel. The inflators have killed as many as 16 worldwide and injured more than 100. The death of the California woman was the 11th tied to Takata inflators in the U.S.

Honda says it has mailed letters, placed Facebook ads, made calls, and in some instances has visited owners. But the results point out that major holes remain in the U.S. safety recall system.