BRZ, FR-S and GT86 Complaining of Rough Idle and Stalling

Buyers of the new SubaruSubaruJapan, 1953 > present34 models
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BRZSubaru BRZJapan, 2011 > present7 photos
, ScionScionJapan, 2002 > present9 models
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FR-SScion FR-S Gen.1, 2011 > present7 versions
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and ToyotaToyotaJapan, 1937 > present155 models
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GT86Toyota GT 86 Gen.1Japan, 2012 > present14 versions
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have gotten what is widely considered a great car, but the owners of the early cars are complaining of rough idling and stalling from their cars. According to Subaru and Toyota the issue is the engine's software mapping that also causes the "Check Engine" light to come on. However, the two companies are giving different solutions to customers. 

According to the two of them, the engine mapping is designed to adapt to the driver. After about 100 miles, the software is meant to freeze the engine map. The problem is that this glitch makes the engine think that it is running outside the frozen parameters and causes the engine to run rough or stall. It also activates the check engine light. 

Subaru will reflash the owners' ECUs to the latest version and claim that will solve the problem. Toyota will only reflash the ECU if the car as less than 100 miles. All other cars will get a replaced ECU. 

"This is not a mileage-dependent condition. No replacement of the ECU is needed at any mileage to rectify the issue. The re-flash is the fix. There is not a defect concerning the ECU," said Subaru National Manager for Product Communications Dominick Infante to Automotive News.

Some Subaru owners on the FT86 Club forum report still having problems after the software reflash. Subaru and Toyota will not report how many complaints they have received or how many cars this affects. 

Source: Car Scoop