Subaru and Toyota are set to recall up to 400,000 vehicles thanks to a dangerous engine defect.

The recall primarily affects the Subaru BRZ sports car, rebadged as the Toyota GT86 and Scion FR-S, as well as the Subaru Legacy sedan and Forester SUV. All vehicles come equipped with Subaru’s FA20 family of 2.0-L 4-cylinder engines that are manufactured in Gunma, Japan.

At issue is a dangerous engine fault that could cause the car to stall without warning. Unfortunately for Subaru, the valve springs were not engineered with sufficient durability and can eventually wear down to the point of fracture. If that happens they will no longer keep the valve closed during the combustion process, which means that cylinder will stop firing properly.

Worse still, the spring could even fall into the combustion chamber, leading to massive damage to the engine. Think “small explosion” leading to lots of metal bits and pieces everywhere.

Subaru and Toyota are not aware of any accidents or injuries as a result of this defect, but you can easily tell how dangerous this issue could be.

RELATED: TOYOTA RECALLS MORE VEHICLES, THIS TIME FOR REAR WHEEL DETACHMENT

In the US, roughly 80,000 Toyota GT86s and 25,000 Scion FR-Ss are part of this recall, along with a whole bunch of Subaru BRZs. The Toyota vehicles were all made between March 2012 and July 2013, while the BRZs were all made between January 2012 and September 2013.

BRZ, FRS
via Auto Trader

The fix is not easy. Subaru has advised it could take up to 12 hours to inspect and repair every affected vehicle. They’ll start contacting owners in December by mail to get their car in to be fixed. All of it will be on Subaru’s (or Toyota’s) dime.

In other recall news, Scion (Toyota's cheap and trendy brand) is recalling xA vehicles made between 2004 and 2006 thanks to an airbag issue. According to the recall, an electric short could damage the airbag's circuitry, preventing them from deploying during a crash.

Once again, mailings to be sent out in December, with airbag control units getting replaced by Toyota free of charge.

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