After installing a new battery, it's common to experience a slight increase in fuel consumption. This happens because disconnecting the battery during replacement resets the ECU, causing stored data to be cleared. As you continue driving, the ECU and TCU will gradually relearn and adjust, eventually bringing fuel consumption back to normal levels.
Additionally, cleaning the throttle body can also have a temporary impact on fuel consumption, though it's not a cause for concern. Many drivers notice a short-term increase in fuel consumption after replacing the battery, which is normal. You can simply continue driving as usual, following your regular habits.
Professional technicians follow standard procedures to disconnect and reconnect the battery, which can temporarily raise fuel consumption. However, over time, the ECU and TCU will adjust automatically, returning fuel usage to pre-replacement levels.
