Service bulletin WQW-58R

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

NHTSA's summary

2.0L DIT Models Only. Subaru of America, Inc. has determined that vehicles affected by this Service Program require ECM reprogramming. This bulletin includes the service procedure for diagnosis and repair of customer concerns involving engine idle roughness or, in some cases, engine noise and/or damage resulting from spark knock (pre-ignition). The Engine Control Module logic has also been optimized requiring the ECM reprogramming. The new logic optimizes the ECM for control of the following parameters: ? Change to Fuel Cut control when fuel level is extremely low / near empty ? Change to improve idle smoothness / quality ? Change to boost pressure control under wide-open throttle (WOT) conditions. Under certain high engine load driving conditions, spark knock can occur which results in elevated cylinder temperatures and pressures. Over time, excessive erosion of the spark plugs and possible damage to the pistons can be consequences of continued operation with these conditions present.

The document

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The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Electrical system, Equipment and accessories

Listing a model year does not mean every vehicle of it is concerned: the document says which.

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

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