2008 Scion xB idle

The Engine Computer lost it memory including long and short-term fuel trim numbers. That data should be relearned as you drive the car. Next time use a memory saver device so all the computers keep their memories alive.

Thank you for the information .

Sorry that I forgot to include information about memory savers. They use a 9 volt transistor battery and plug into the cigarette lighter. The only thing you have to check for is that the lighter works with the ignition switch off so the transistor battery's current can feed the computer memories. If the ignition switch has to be on for the lighter to work, that little battery won't be able to power all the stuff that turns on.

Thank you very much. I have a 12v jumper I made that works great but as usual the battery croaked with out warning and Advanced auto parts didn't have anything , So trouble. Thanks again. Intruderjack

If it doesn't begin running correctly, you may need to scan it for trouble codes to see if the computer has logged any errors
The guide below gives the most common causes for misfires

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

wait till engine has cooled(next morning), start xb,(dont touch anything, no buttons,gas pedal, brake pedal, a/c controls,nothing)let it run, appro. 15 minutes, or until you hear or see cooling fans kick on, as it runs youll hear it smooth out. once fans kick on, turn car off,take key out,put key back in and you should be good to go.once you replaced battery as stated above you wiped out idle curve, it has to be relearned,i tried driving mine for week and a half ,it never smoothed out (car shaking idle and horrendous noise). found this tip after an hour of searching and solved my issue immediately

Dandy. Thank you for posting that information.

https://m.youtube.com/watch?v=_S9B3IhK_Tc

Hello there. Just to add some bit of information, I have seen this condition after a dead battery or replacement. The throttle body would need to be cleaned out. The learn values had compensated for the dirty throttle. When disconnecting a battery or replacing battery all the values reset back to factory. If the throttle is dirty you will have idle issues. Cleaning the throttle body should correct this concern.

Here is a link that will give you the basics on cleaning out the throttle:

https://www.2carpros.com/articles/throttle-actuator-service

Hope the information helps out. Let us know please.