You would think it would be stored in memory without needing a battery. Some cars adapt to the way you drive and store somethings in memory. When you disconnect the battery it looses this memory and the engine runs sort of rough for a while.
Then again, with the experiances I have had in industrial electronics, even the very high dollar computer systems will have a glich in them, have to have the power cut off and back on to reset them. Some would loose all their memory and have to be reprogrammed. For others it was like a computer reboot and starting from a known point in the programming. We had two pieces of equipment that anytime something went wrong, the first thing todo was to cut the power ,count to 10 and turn th epower back on. This fixec the problem in many cases.