Many Mainers don’t know yet if they are affected by a massive recall of a defective airbag that was used in nearly 34 million cars nationwide, and relatively few are asking about the recall so far, according to two of the state’s largest dealerships.

What is clear is that many motorists could be in for a long wait to have the equipment replaced if it’s needed.

Takata Corp. announced an expanded recall Tuesday of faulty airbag inflators installed in a wide variety of makes and models of vehicles on American roads. The Takata-made modules contain the explosive chemical that inflates an airbag in a few milliseconds after a collision. It is now the largest auto recall in history, and it is expected to take years to replace the recalled parts.

Although federal safety officials have warned that the defect can case fatal injuries, Mainers so far are only trickling into car dealerships to have the units fixed, said Adam Lee, owner of Lee Auto Malls, whose group of dealerships sells about 10,000 cars annually in Maine. At his Toyota dealership in Topsham, for example, about five or six people a day are calling the service department to ask about the recall fix.

“We’re surprised at so few calls,” Lee said.

The malfunctioning airbags have been found to expand with greater force than normal when they deploy, and can send bits of steel flying toward vehicle occupants. Investigators believe the malfunction occurs when the explosive chemical inside the airbag, ammonium nitrate, is degraded by exposure to humidity and moisture.

So far, the faulty airbag inflators have been linked to six deaths and injuries to about 100 people.

Takata at first restricted its recall to 17 million cars in the Southern and Gulf Coast states where hot, wet weather could contribute to a greater likelihood of airbag failure. But it doubled the number of vehicles this week and made the recall nationwide.

Although the recall expanded, motorists and car manufacturers are waiting to find out which vehicles are affected. Officials with Takata have said it will take several days to pinpoint which cars within each model year have the faulty airbags.

Complicating the process further is a patchwork of procedures that differs for each of the 11 car manufacturers whose vehicles are affected, making it confusing for some motorists to figure out if their vehicle is among those being recalled.

OWNERS NOT IN A RUSH FOR FIX

Federal safety officials have asked people to do the legwork themselves by going online and entering their unique Vehicle Identification Number into a database to find out if their car is affected. However, that website temporarily went dark this week when it was apparently flooded with traffic. And the National Highway Traffic Safety Administration says vehicle owners will have to check the database again in the coming days and weeks as vehicles are added to the list.

Some Maine motorists who have been notified by manufacturers or who found their vehicles in the online database are getting the faulty airbag inflators fixed.

“We do a couple a day,” said Robert Ramos, general manager of Prime Toyota in Saco. “We don’t have people lining up to get in to get it done. In this latest round, (the manufacturers) haven’t really clarified what vehicles are going to be affected.”

Lee chalked up the slower-than-expected response in Maine to two factors: People are experiencing recall fatigue after constant media coverage of past recalls, and the incredibly low chance that a customer personally knows someone who was harmed by the defective equipment.

“I kind of believe that the level of stress (over a recall) for the average customer is relative to how remote the incident seems to people’s lives,” Lee said.

Out of the roughly 16 million cars sold to consumers annually and the roughly 253 million vehicles on the road, that represents a tiny risk.

Some motorists approached the recall with the same long view.

“There’s so many things in life that are screwed up. That’s not a priority,” said Walter Kuhn, of Raymond, who owns a 2005 Toyota Camry.

Brewster Taylor, 64, who was visiting Portland from Alexandria, Virginia, said he felt similarly confident about the safety of modern cars, compared with how vehicles were designed and manufactured when he started driving decades ago.

“I remember when cars were much less safe. The first car I drove was a Corvair,” Taylor said, referring to a Chevrolet model produced in the 1960s that was the subject of a national campaign assailing its safety and handling.

Connie Tidd of Portland said she bought a new Honda CRV in February, and is leaving it up to Honda to contact her if the need arises. “I’m assuming they’ll tell me if something is wrong,” Tidd said.

Other drivers weren’t as trusting.

Libby Lauze, 38, of Portland, was concerned enough about the recall to go online and try to find out if her 2005 Subaru Outback would need to have its airbag inflator replaced. The federal website was so flooded with users, she couldn’t get through.

“It’s almost more concerning to learn about how long it’s going to take to get a slot to get it fixed,” Lauze said.

How long vehicle owners have to wait for the fix will vary because each manufacturer is handling the recall differently. Some have made it a priority to ship replacement units to Southern states with hot, humid climates, for example.

TRYING TO ACCELERATE PROCESS

To remedy the patchwork of approaches by automakers, the National Transportation Safety Board on Thursday said that for the first time in history, it is pursuing legal authority to take on a larger role in controlling the production, delivery and installation of the replacement airbag inflators. The agency wants to accelerate the recall process, which could take more than 2½ years to complete at the current pace of production of replacement parts, according to The Associated Press.

“To save lives and prevent injuries, defects must be repaired,” said NHTSA administrator Mark Rosekind, according to the AP. “This is an enormously complex situation.”

Lee’s Toyota dealership in Topsham can only get two replacement units per day. On the other hand, Lee said, some customers of his Honda dealership haven’t responded to the notices about the recall and 100 replacement parts are waiting on a shelf, each assigned to a customer.

“I think we’ll be doing this recall five years from now, still,” he said.