GM recalls may continue through mid-summer: Expert

General Motors, which has already recalled almost 16 million vehicles worldwide this year, is expected to continue issuing more recalls through mid-summer, according to a research note from Barclays.

Barclays analyst Brian Johnson met with senior management at GM and said the automaker is using new techniques to uncover potential defects. As a result, "It is possible that GM may issue further recalls for vehicles, which may have already been recalled."

In each of the last two weeks the automaker has recalled more than two million vehicles for a variety of safety issues. So far this year, it has recalled about 13.8 million vehicles in the U.S. through 29 separate recalls.

Earlier this week, GM also increased the charge it expects to take in the second quarter to about $400 million, mostly to handle repairs related to the recalls. Including this amount, GM has already this year taken at least $1.7 billion in charges related to the recalls.

One reason why the automaker's flurry of recall announcements may not slow down is because it's using new techniques to identify potential safety problems. For example, the automaker is using data mining techniques to review complaints, warranty claims and other information about current and previous models to identify safety issues.

Read MoreGM recalls make it tough to rent a car

GM is hoping to change its perception with the National Highway Traffic Safety Administration, which oversees vehicle recalls. During the ignition switch recall investigation, a NHTSA official accused the automaker of being "slow to act" on potential recalls.

GM has added 30 additional in-house experts from a wide range of departments to further analyze potential defects. GM's head of product development, Mark Reuss, is leading a five-member team that will make decisions on recalls.

Read MoreToo many recalls: Fiat Chrysler CEO

"GM is trying to aggressively issue recalls for items as soon as they learn about it, rather than batching the items for a vehicle and waiting—even if there may be negative optics around such a strategy," Johnson wrote.

Earlier this week, Fiat Chrysler CEO Sergio Marchionne told CNBC the industry is being hypersensitive and recalling too many cars.

Despite GM recalls dominating the headlines, sales have not slowed down. In fact, showroom traffic has been steady.

"GM sales this month are outperforming the industry right now," said Jeff Schuster, senior vice president of forecasting at LMC Automotive. "GM's added a few extra deals to help draw in buyers, but it has not had a big escalation in incentives."

Memorial Day weekend is traditionally one of the busiest weekends of the year for auto dealers. This year, J.D. Power predicted auto dealers will have one of their strongest Memorial Day weekends in more than a decade.

Morgan Stanley analyst Adam Jonas said a Chevy dealer in Canton, Ohio, is noticing stronger traffic in part because GM is offering supplier pricing and additional incentives.

Read More'We had no idea' about faulty switch: Car czar

"We had already felt that business was picking up, but the extra traffic and incentives are adding an extra amount. One notable exception would be the Chevrolet Cruze, which has really dried up recently," the dealer said.

Year-to-date, General Motors sales are up 0.1 percent while the industry overall is up 3.1 percent, according to research firm Autodata.

—By CNBC's Phil LeBeau.

Questions? Comments? BehindTheWheel@cnbc.com.