At 60 K the dealership performed the software update per FCI. After many complaints of bad performance FCI came out with another update. After update my milage dropped from 21.7 to 15.1 at 90 K. I never cleared my "A" odometer so the 15.1 is correct. Told dealership and all they did was shrug their shoulders and said we have many complaints on the issue. It also has been giving me regen messages more often. Any help would be appreciated. Also if I buy a tuner what is good and will it affect the extended warranty on the engine?