What the issue Lenna? What code are your receiving? Usually the ECM is replaced. A used unit is usually the way to go. To reprogram you start the car and slowly turn on all accessories for the new unit to "learn" the new parameters.
If the ECU is bad, it must be replaced- if you are looking for more performance from the engine, there are "chips" for sale out there in webland that can be added to reprogram the air and fuel mixtures in the engine
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