After changing the battery, the idle oil increases and decreases after driving.

Normal phenomenon. After replacing the car battery, the idle speed is unstable. The easiest way is to let the car run a little or clean the throttle. If it is not good, you need to use a special computer to adjust and match the throttle bypass valve screw. There are various troubleshooting methods, which can generally be solved by "manual adjustment, computer recovery or other means". Manual operation can be resumed by turning off ETCS or EFI that controls the throttle valve, depending on the vehicle model. The fuse lasts for a certain time, for example, about two or three minutes.