Q: Reduced engine performance that smooths out after 40 MPH until acceleration.

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Vehicle runs roughly and has a read out thats says reduced engine performance. Initailly, the vehicle runs rough at 40 mph, then smooths out until I try to accelerate.

Hello, being that the engine and transmission are computer controlled, a scanner needs to be connected to retrieve codes. If there are no codes present the technician will be able look at data retrieved by the scanner and come to a possible solution. When symptoms like this occur with the "reduced engine performance" message, the vehicle is going into limp home mode trying to protect the engine and or transmission from further damage. You should enlist the aid of a mechanic to inspect your engine.

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