The National Highway Traffic Safety Administration said it has stopped many of the activities that help keep motorists safe in their vehicles.
In a statement, the agency said it has stopped issuing recall notifications, stopped investigating potential automotive defects and would no longer evaluate consumer complaints "due to a lapse of Federal Government funding."
Consumers can continue to file complaints on the agency's website, but they will not be investigated until funding is restored. Likewise, automakers can continue to announce their own recalls to the general public, though not all of them elect to do so.
"If an automaker does a recall, it might be because they know government investigators are on the trail," said Clarence Ditlow, Executive Director of the Center For Auto Safety, who estimates 25 to 40 percent of all recalls are spurred by government investigations. "Without those investigations ... in the long term, it could significantly endanger consumer safety."
NHTSA also said that rulemaking will be postponed, as well as new car assessments that include crash tests and star ratings that many use to make car-buying decisions. In the short term, that may not mean much for motorists, but if the shutdown lingers, it could hurt consumers.
"For a consumer who goes and buys a car today, then finds out a month from now it was a poor performer on a test, they're not going to be able to get their money back," Ditlow said. "So it's a raw deal."
On its Facebook and Twitter accounts early Tuesday, NHTSA said that it would not post updates or respond to comments. Of the agency's 597 employees, 333 are furloughed, according to the Department of Transportation's plan for operating amid lack of government funding. Some operations funded by the Highway Trust Fund will continue.
Some of the government's other transportation-related functions remain open despite the shutdown. Air-traffic controllers will remain on the job, though approximately 3,000 aviation safety inspectors will be temporarily furloughed. Fifty-two percent of the Federal Railroad Administration's 886 employees are also furloughed.
While the government is hobbled, the shutdown is not expected to affect the number of consumers buying new cars in what has been a banner year for auto sales.
"The American people might be questioning their faith in government right now, but they still have confidence in the economy," said Dr. Lacey Plache, chief economist at Edmunds.com. "American car buyers have been remarkably resilient in the face of the Congress' antics over the past year. There's no reason to believe that auto sales will suffer in the coming days or weeks as this mess gets sorted out in Washington."
Pete Bigelow is an associate editor at AOL Autos. He can be reached via email at email@example.com and followed on Twitter @PeterCBigelow.