Mazda Canada is recalling more than 42,000 vehicles to fix a mechanical malfunction that can cause engines to stall.
The recall affects 2018 and 2019 Mazda3, Mazda6, and CX-5 models equipped with the company's 2.5L four-cylinder engine.
The problem stems from a fuel-saving cylinder-deactivation function. When the engine transitions from cylinder-deactivation mode to normal, full-power function, a component in the intake valvetrain can become misaligned or detach and interfere with other parts, causing a misfire, loss of power, or stalling. The worst-case scenario is the engine will stall and then not restart.
Mazda Canada and Transport Canada issued a joint recall in late June, but we became aware of it yesterday when the company's North American division (which oversees operations in the US and Mexico) publicized its own recall notice through the National Highway Traffic Safety Administration (NHTSA).
According to the NHTSA, Mazda's knowledge of the problem dates back to early 2018 when it began receiving reports of noisy engines and intake valvetrain failures. Mazda North America submitted its recall intention to the NHTSA in late June but the company did not publicize it widely until this week.
Mazda Canada says it will notify affected owners in this country by mail. Their fix is to update the powertrain control module's software with improved programming for the cylinder deactivation system.