Despite at least 19 reported instances of Chevrolet, Cadillac, Hummer and Buick vehicles inadvertently deploying their side curtain airbags, General Motors has not investigated any problems with its airbag sensors, beyond one recall for a single model in May.

Five of these cases involved late-model Chevrolet Camaros and Cadillac CTS-Vs. At least three Camaro coupes, including one tested by Edmunds last year and another by Canadian automotive site Sympatico in 2010, blew their side curtain airbags during standard performance tests. A third Camaro deployed its airbags in August 2011 during a drift exercise in Michigan, as shown in the photo above and the video below.

In May, GM recalled 4,304 2013 Chevrolet Malibus to reprogram the airbag sensing and diagnostic module, which detects whether crash forces are sufficient to deploy the airbags. In the recall, which began in June, GM said that after hard braking, the module can "reset itself" and cause the curtain airbags to deploy "during an aggressive turning maneuver."

However, when asked if GM would consider extending this recall to other models, spokesman Alan Adler said that the Malibu recall was for a "specific set of circumstances" and that there were "no current investigations of inadvertent airbag deployments."

Other GM models sold within the past five years have been similarly affected. In May 2011, an owner of a 2009 Chevrolet HHR SS wrote on the ChevyHHR.net forum that his curtain airbags deployed during a hard left turn, during which he slid slightly but was not in danger of a collision. (Note: We could not find a report filed with the National Highway Traffic Safety Administration that involved a Chevy HHR SS in similar circumstances.) In March 2011, an owner of a 2011 Buick Regal reported to NHTSA that four side airbags deployed after the owner drove over a "road bump."

Airbag experts and automotive engineers say that while it's rare for airbags to deploy in this manner, it can happen because of faulty wiring. In 2011, Ford recalled 1.4 million F-Series pickups and Chrysler recalled 300,000 minivans, both for airbags that could deploy inadvertently due to electrical issues. However, Adler said accidental deployments also could occur during aggressive driving.

"Inadvertent airbag deployments do happen from time to time, especially when a vehicle is being tossed around and the system senses a rollover or crash is imminent," he said. "This can even happen when taking a highway on- or off-ramp too fast with too much lean."

Alby Berman, a spokesman for Takata, which supplies airbags for the Camaro, said that while side airbags require a faster reaction time than front airbags -- as little as 10 milliseconds from sensing an impact -- they are not inherently tougher to program. "Side airbags and frontal airbags have been around a long time," he said. "You just have to make the decision in time."

Berman said Takata does not supply airbag sensors to GM. Citing rules in its contract, Continental Automotive, named by NHTSA as supplying the 2013 Malibu with airbag sensing and diagnostic modules, refused to comment on the recall or say whether it supplied modules to other GM vehicles. GM would not comment on its airbag sensor suppliers.

Jake Fisher, a senior automotive engineer for Consumer Reports who has tested more than 1,000 cars, said he was surprised that performance cars such as the Camaro were deploying their airbags. "That, to me, is a malfunction," he said. "There's plenty of Mustangs and Challengers and Porsches that drive like that and don't blow [the airbags]."

Fisher said that in his 13 years with the magazine, other car safety features have inadvertently gone off during testing -- such as the Mercedes-Benz Pre-Safe system, which cinches the seatbelt and moves the seat to prepare for a collision -- but that no airbags ever deployed under his watch. Several GM vehicles, however, had automatically contacted OnStar even though there no accident had occurred, he said.

NHTSA does not have any pending airbag investigations against GM and would not comment on whether it was considering one. While there are no specific number of reported complaints that trigger an investigation, NHTSA is investigating the 2012 Hyundai Elantra for side curtain airbags that deploy improperly, based on a single complaint.

NHTSA has collected nine owner complaints of inadvertent side airbag deployment on the 2007-2009 Hummer H3 and three similar complaints on the 2007-2008 Chevrolet Avalanche, yet the agency has not opened an investigation into either model. All of these cases, which occurred between May 2007 and November 2011, explicitly described the side curtain airbags deploying without any collision or potential rollover occurring. According to the reports, some of the vehicles were not even turning, but were traveling straight or had struck a pothole immediately before the airbags deployed.

Upon inspecting the vehicles, some GM dealers determined the airbag sensors were faulty, according to the reports. Others could not diagnose the problem. On public forums, some Hummer and Chevrolet owners said they were left to pay part or all of the repair costs due to insurance companies blaming GM for the damage and refusing to pay, GM denying warranty coverage based on black-box data, or a combination of the two. Adler would not comment on any specific warranty claims or if it had paid for repairs, but said the company's decision to cover damage due to inadvertent deployment "often rests on what the event data recorder shows."

Many of the owners suffered injuries from the airbag deployments, including bruising from the seatbelt pre-tensioners, as shown by Edmunds. In one highly publicized case, GM paid an undisclosed settlement to Tammy Posnick in Syracuse, N.Y., and bought back her 2007 Avalanche.

"I had no idea what just happened, I was driving along, nothing," she told Syracuse TV station WSYR last year. "I didn't hit anybody, nobody hit me, nothing, and I said the airbags just went off."

GM has recalled several models for airbag problems in the past two years, including the Cadillac SRX and first-generation Cadillac CTS, but none of those recalls was related to inadvertent deployment caused by faulty sensing modules.

In July, Hyundai recalled more than 22,000 Sonata sedans for side curtain airbags that could deploy inadvertently. NHTSA also is investigating the 2002-2003 Jeep Liberty for front airbags that could deploy by accident.