Last month’s recalls of the Cobalt and five other models encompassed model years 2003 through 2007. G.M. faces numerous investigations, including one by the Justice Department looking into the company’s disclosures in its 2009 bankruptcy filing as well as what it told regulators.

In the bankruptcy agreement, G.M. was shielded from liability for accidents that occurred before July 10, 2009.

“We are conducting an unsparing, comprehensive review of the circumstances leading to the ignition switch recall,” G.M. said in a statement on Monday. “As part of that review we are examining previous claims and our response to them. If anything changes as a result of our review, we will promptly bring that to the attention of regulators.”

G.M. has said it has evidence of 12 deaths tied to the switch problem, but it has declined to give details other than to say that they all occurred in 2009 or earlier. It says it has no conclusive evidence of more recent deaths tied to the switch.

Image Christopher Hamberg, 18, died in a Cobalt accident in June 2009. Credit... Hamberg Family

“We are doing our best to get this right, which means reviewing the data with care,” the company said in its statement. “Not every Cobalt accident is a result of a faulty ignition switch. Accident claims and E.W.R.” — Early Warning Reporting — “data are unique, with their own set of facts and other relevant factors. It is wrong to use this information on a speculative basis. Each requires additional analysis and this will be a part of our review.”

It was unclear how many of the 26 deaths since the 2009 meeting were related to the faulty ignition, but some appeared to fit patterns that reflected the problem, such as an inexplicable loss of control or air bags that did not deploy. In some cases, the drivers had put themselves at risk, including having high blood-alcohol levels or texting.