The National Highway Traffic Safety Administration is intensifying its investigation into stalling Toyota Corolla models. According to the Associated Press, the agency has opened what it calls an engineering analysis into 1.8 million Corolla and Matrix models sold between 2005 and 2007. So far, NHTSA has received around 163 complaints about stalling in those vehicles, and the government seems to believe the problem may be due to a faulty coating on the vehicle's circuit boards. It's also possible that a crack could develop in a particular glass coating in the vehicle.

NHTSA hasn't gone so far as to issue a recall in this particular case as its research into the problem is ongoing. Previously, investigators were only looking into Corolla and Matrix models produced in 2006, though the recent expansion indicates that the issue may be more widespread than previously believed.

Last we heard, Toyota was considering a voluntary fix for the problem, though since then nothing has come up in terms of a proposed solution from the carmaker. Back in March, NHTSA said that the problem doesn't pose any danger to drivers.

[Source: Associated Press]