TM Toyota Motor Corporation

A government audit found continued lapses undermining U.S. auto-safety regulators' efforts to protect motorists from vehicle defects, including a failure to follow through on some promised reforms.

The U.S. Transportation Department's inspector general in a report Friday said the National Highway Traffic Safety Administration hasn't yet started a training program for investigators aimed at helping them better spot safety risks in automobiles. The agency's investigators also don't properly document evidence such as consumer complaints and meetings with auto makers that could better assess or support adequacy of probes, the report found.

The inspector general report followed a 2011 audit of the agency launched in the wake of unintended acceleration issues in Toyota Motor Corp. vehicles that were later settled. Friday's report also follows a separate audit of car-safety regulators in June amid regulators' failures to spot defective ignition switches in older General Motors Co. cars now linked to 124 deaths.

A NHTSA spokesman said the agency agreed with the inspector general's recommendations and plans to implement them, as well as those from the June audit, by June 30. They include launching a training program and better assessing compliance with internal policies. A separate internal NHTSA report last year found other shortcomings and made recommendations for improving the agency's work that are in the process of being put into effect, the spokesman said.

NHTSA Administrator Mark Rosekind has taken an aggressive approach to ​trying to ​overhaul​ the agency and more actively police auto makers​ since taking the helm in late 2014. The agency in November fined and ordered Takata Corp. to meet certain conditions for unprecedented recalls of rupturing air bags and in July hit Fiat Chrysler Automobiles NV with a large penalty and other measures for lapses in nearly two dozen recalls covering millions of vehicles.

Mr. Rosekind has brought different departments together in meetings and often pushed staff to question both assertions from auto makers and their own approaches to regulating the industry. "Those are the pieces that have been different, which is being more inclusive, getting hard questions asked of ourselves instead of waiting for someone else to do that," he said in an interview earlier this year

Fridays' inspector general report found NHTSA employees embraced all recommendations the 2011 audit made but haven't carried all of them out. The agency, for instance, has mostly failed to document reasons for blowing through its own investigation deadlines.

The report highlighted NHTSA failures to launch a training program for investigators to make sure they can properly spot safety risks. NHTSA investigators "may not be sufficiently trained to identify and investigate potential vehicle defects, or ensure that vehicle manufacturers take prompt and effective action to remediate issues," the report found.

The inspector general's June audit found investigators charged with spotting so-called early warning reporting data had no training or background in statistics. Auto makers are required to report deaths, injuries, property damage, consumer complaints and warranty claims to help regulator spot possible safety problems.

Regulators fully met some previous recommendations. The report found NHTSA staff consistently recorded ​each review of consumer complaints and tracked them to associated probes. The agency also successfully ​conducted a workforce assessment and coordinates well with foreign countries.

Write to Mike Spector at mike.spector@wsj.com

(END) Dow Jones Newswires

February 26, 2016 11:45 ET (16:45 GMT)

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