Mitsubishi Repair: Car wont run after Dead Battery, battery failure, old battery

Question
Have 2001 Gallant V6, the battery died and after purchasing new battery and installing.  The car immediately starts and run until warmed up.  Once warmed up it will not idle.  The car was running very good prior to the battery failure, what could cause this situation.  

Answer
Paul: My question to you would be what caused the old battery to be replaced? Was it old, would not take a charge anymore or what? Could be you have a bad sensor, because something is not telling the computer of your car that it is warmed up. So the mix is to lean or to rich. Which would make it not idle right. I would have the car's sensors checked. Could be the battery going has nothing to do with the idle problem but just showed up at the same time. The battery in a sense is kept charged to keep the power going to things such a lights, to help power the starter to start the car also keeps the computer powered too. But idle no, other than those sensors and of course the computer. So I would be looking someplace else for your problems with the idle. You should get a manual for your car, as I tell everyone to get one of those. It helps you understand what is going on with your car and things to look for. So I would start there and see what it tells you. Hope this helps and good luck!