The recall of the Corolla and Matrix cars adds to the 11 million vehicles Toyota has recalled in the past year, mostly for unintended acceleration, denting its reputation for quality and gaining intense scrutiny by U.S. safety regulators.
General Motors Co also said on Thursday that some 200,000 Pontiac Vibes, a sister car to the Toyota Matrix, would be recalled in the United States and Canada because of the same issue.
Toyota said it had unconfirmed reports of three accidents and one minor injury in the United States in connection with the problems with the units on vehicles from the 2005 through 2008 model years. It will replace the modules.
The U.S. National Highway Traffic Safety Administration on Aug. 18 intensified a probe into reports of stalling in the vehicles from the 2005 through 2007 model years, upgrading a preliminary investigation opened in November 2009.
"The engine can stall at any speed without warning and not restart," NHTSA said in a report on its website.
Toyota spokesman John Hanson said four of 32 engine control modules obtained from cars in service and four malfunctioned during tests that subjected them to extreme heat and cold, prompting the decision to replace the components.
The recall covers 1.13 million vehicles in the United States and 200,300 in Canada, Toyota said. Toyota Canada said it had no reports of accidents or injuries.
Toyota was the builder of record for the Vibe, which was produced at the New United Motor Manufacturing Inc plant in California that had been a joint venture between the Japanese automaker and GM. Toyota also built Corollas at NUMMI.
Toyota said cracks could develop in some of the connections on an electronic component that prevents excessive voltage, in some cases resulting in harsh shifting, a failure to start the car or stalling.
Toyota identified the component manufacturer as Delphi in a letter to NHTSA on Thursday. The vehicles under the U.S. recall were built from April 2004 to early January 2008. It opted to conduct a recall on Aug. 19.
James Bell, executive market analyst at Kelley Blue Book's kbb.com, said Toyota had been moving beyond the recalls that dented its reputation before the recall, but its candor would go a long way toward mitigating long-term damage.
"As if to rub gasoline in Toyota's already painful wounds, this round of recalls is in response to consumer complaints of unexpected and therefore dangerous engine stalling, rather than the equally unexpected acceleration problems earlier this year," Bell said.
Toyota said owners would receive notices about the recall starting in mid-September and would receive a notification later when replacement parts are available.
Hanson declined to discuss the cost of the recall, which will include the modules as well as labor.
GM discontinued the Pontiac brand last year and Vibe owners also will receive a recall notice starting in mid-September and one when the module can be replaced, GM spokesman Alan Adler said. GM dealers will perform the repairs.
