I've got a problem with my battery before for my 97 lexus lx450.So I decided to pull it out and charge it overnight.When I installed the charged battery,after few days,It's hard to restart again the truck.So,I put a new battery(not actually new but it came from my 98 4runner)and starts right away.Now,the problem is I got a low idle..sometimes it stalls in the stop light.I checked the battery,alternator..and works fined.My brother told me,it might me the ECU coz u took out the battery overnight without installing a back-up.I just did my PHH two days ago..now the situation gettin worsen.I checked the related forum here,but can't get a clear answer.I plugged my OBDII scan and throw me a code P0172 MAF sensor bank1.But,I just wanna know if my brother was right,coz before I don't had a problem like this..it only start when I took out the battery for re-charging.What do you think?please advise.