REPLACED MY BATTERY ON MY 2004 F150, NOW I GET SERVICE ENGINE SOON

Question: I JUST REPLACED MY BATTERY ON MY 2004 F150,4.6 LITER NOW MY TRUCK IDLES REALLY LOW,I HAVE DRIVEN THE TRUCK ABOUT 60 MILES SINCE I CHANGE BATTERIES NOW I GET SERVICE ENGINE SOON DISPLAY TODAY THE LIGHT JUST CAME ON BUT THE LOW IDLE WAS FROM THE BEGINNIG OF THE BATTERY CHANGE Answer: IN ORDER FOR THE LIGHT TO COME ON AND SET A CODE, THE ISSUE HAS TO THERE FOR A CERTAIN LEGTH OF TIME. FOR EXAMPLE A MISFIRE MAY OCCUR BUT UNTILL IT OCCURS 100 TIMES DURING 400 CYCLES IT WILL NOT SET A CODE. The first thing to do would be to extract the check engine light codes. This can be done with a Scan Tool or you can take it to an Autozone and they will do it for free. Once you have the code it will help guide to the problem area. Trouble Code Descriptions