It’s possible for a car engine to be too quiet. Two people so far have suffered from carbon monoxide poisoning when their Chevrolet Volt cars switched imperceptibly to their gasoline engines. When this happens, the engine remains so quiet that it’s possible to forget that the car is running, and the combustion engine gives off the silent gas that can be deadly in an enclosed space. Like a garage.

Chevrolet is recalling Volt cars from model years 2011 through 2013, but the only repair is a software upgrade that will limit how long the car can run while parked. The number of cars affected has been reported as both 50,249 and 64,000: the discrepancy probably represents cars sold outside of the United States.

The dangers of electric and hybrid cars being too quiet go far beyond the walls of owners’ garages: it was almost four years ago that the NHTSA noted that they have a higher rate of accidents involving pedestrians, because people on the street–and not just blind pedestrians–can’t hear them.

General Motors also recalled some Chevrolet Trax and Buick Encore crossover vehicles to correct a possible problem with power steering, but those vehicles hadn’t been sold to the public yet, presumably making it a lot easier to get the recalled vehicles in to the service department.

GM recalls Chevrolet Volt over carbon monoxide [USA Today]
GM recalls 64,000 Volts over carbon monoxide risk [AutoNews]

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