On my 12 Scion tc When stopped in Drive or Reverse and foot on break the car idles roughly at about 600.. when coming to a abrupt stop it goes down to 500 but never dies and goes back up to 600. Also having the AC on help idling at 700-800. Soon as i release the break idle goes up. No CELbut my bluetooth reader throws a permanent code p0102 something about the MAF sensor which i already replaced with a new one but did not resolve the idling issue and the code is still there.
Today i noticed when stopped and the car is idling low it goes even lower when i turn on the fans all the way or roll both windows up and down. So i took it to autozone and they did 5 tests on the alternator, 3 out of those 5 tests failed so im assuming alternator is bad. Although i see no flickering lights or any other signs of electrical issues. The battery is new at 100% charge. Also cleaned the TB but never actually took it off the car just cleaned the inside as far as i could reach. Also replaced the air filter.
Any advice?