Thank you for choosing JustAnswer and allowing me to help you resolve your Toyota questions!
What exactly is the nature of the problem with your car?
Has the check engine light been on recently if so do you know the code numbers? How many miles on the vehicle and do you have any recent service history?
That is what I suspected ie battery replacement. The computer lost the memory setting for the Idle. It will eventually relearn. There is no idle adjustment. This is a drive by wire throttle and the computer opens the throttle plate to control engine speed. If you are handy my suggestion is to remove the boot going to the throttle body. With the key in the off position use a clean rag and some carburetor cleaner to clean the varnish from the throttle plate and bore. You can push the plate open with your finger. Then remove the battery cable again for a few minutes then start the engine and rev a few times to clean the excess cleaner and the idle should straighten right out for you. This is a common procedure to repair the situation quicker.
That is good to hear glad it is now idling normal.