I need to know , how common is it on lexus/ toyotas (2013 ES350 )that they need to relearn the idle when you change the car battery.
i trust my mechanic , he said he will clean the throttle body and relearn the idle
else if battery changed car might loose its settings and might stalled on a stop and won’t start
how much is truth to this, has anybody faced this issue , should i replace by myself and don’t bother about it.
please advice by experience
Yes, that is a true statement. When you disconnect the battery and reconnect it, you are clearing the saved "adapted" data on the ECU (volatile RAM that the battery retains). When the volatile RAM is wiped from disconnecting the battery, the ECU needs to relearn all the parameters that allow the engine to idle perfectly. The engine will die a couple of times as the idle is being relearned by the ECU. It may also die when you come to a stop while driving if the idle hasn't been relearned yet.
However, newer cars have ECU(s) that retain these adaptive parameters in a non-volatile RAM, so if the battery does get disconnected or dies, the engine will still idle perfectly after starting it up again.
Hook up an OBD2 memory saver while replacing the battery.
