A thousand complaints about the sudden loss of power steering in one vehicle made from 2007 to 2011.

Dozens of complaints about intermittent loss of electrical power in a 2012 model.

Inexplicable headlight outages. Brake failures possibly linked to ice. Carbon monoxide build-up serious enough to cause a driver fatigue, nausea and headache.

All are examples of problems in cars or trucks traveling U.S. highways. All were recently brought to the attention of the National Highway Traffic Safety Administration. All are problems I can't detail for you, identifying makes and models, because none ever prompted a formal inquiry by NHTSA's Office of Defects Investigation, according to a report last month by the Transportation Department's inspector general.

Those problems may not sound quite as scary as defective Takata air-bag inflators, subject of a massive recall because they can send shrapnel flying, or faulty GM ignition switches that suddenly cut power, causing loss of control and stopping an air bag from saving a driver.

For that matter, none may reflect a serious problem in a vehicle's design, manufacture, or parts. The trouble is, it's impossible to say for sure - which is why their mention in the audit is more evidence that something is very wrong at one of the nation's most important, and most inscrutable, consumer-protection agencies.

Or many things. For years, advocates such as Clarence Ditlow, of the nonprofit Center for Auto Safety, have warned that NHTSA epitomizes the problem of the "captive regulator" - an agency whose close relationships with the companies it oversees tends to make it more responsive to them than to the public it's duty-bound to protect.

Since the Reagan era, the agency has seemed separated from automakers less by an arm's-length relationship than by a revolving door. Top NHTSA officials go on to serve as consultants, lawyers, and expert witnesses for the industry. Former automaker employees sometimes fill key positions at the agency.

The GM ignition-switch defect reflects some of the agency's most deep-seated problems. So far, at least 114 deaths and 229 injuries have been linked to the defect. But the problem was first reported to the Office of Defects Investigation more than a decade before GM finally got around to recalling affected vehicles last year.

The inspector general blames shortcomings largely on data collection and analysis at that crucial NHTSA office, whose screeners are each expected to process an average of 330 complaints every day.

Still, there's no good excuse for the kinds of blatant warnings that were overlooked, such as a June 2007 state trooper's report on a fatal accident in a '05 Chevrolet Cobalt that identified the car's ignition switch as a possible reason its air bag never inflated. Two staffers "did not note this potential link when documenting their reviews."

Even warnings by GM personnel went for naught, perhaps because of inconsistent coding.

One reported that an '05 Cobalt "stalled on a highway when the employee's knee 'hit the GM brown leather key holder,' " the audit said. That was coded as an "Engine and Engine Cooling" issue.

Another reported that an '06 Pontiac Solstice "turned off several times while driving when his knee hit the accessories attached to the key ring." That was classified as an "Electrical" problem.

Mark Rosekind, a respected safety researcher who in December took over as NHTSA administrator, told a Senate panel last month that he was working to address flaws that slowed the agency's responses to the Takata and GM defects.

Connecting the dots on complaints should always be among any safety agency's priorities. But other dots are also perilous to ignore.

One is this overhyped divide: that conservatives want "smaller government" and liberals "the nanny state." Aside from a few ideologues, sadly some in Congress, chances are no one wants NHTSA to lack what it needs to oversee products involved in 30,000 deaths a year.

Yet that's what sequester-era politics have wrought. NHTSA's vehicle-safety budget, already a paltry $134 million, dropped this year to $130 million.

"You have too many complaints and not enough people," Rosekind says.

Another dot is a culture at NHTSA that appeases vehicle makers, who want to avoid costly recalls and seem to think they benefit from an underfunded regulator whose failures make it easier to sweep problems under the rug.

"I was trying to understand how you could have a GM defect that for over a decade was not acted upon by either GM or NHTSA," says Louis Lombardo, a retired NHTSA safety researcher who founded CareforCrashVictims.com.

"You hear in all these cases that they're looking for a root cause," Lombardo says. "The root cause is greed."