So i have a 96 ford taurus. it has almost 100,000 miles on it. Im not quite sure what is wrong with it but most of the time when it is warm, and at an idle it will stutter. What happens is, at a stop light when it is warm and idleing it will bog down and stutter. Itll bog down to about 400 rpms or so for about no more than 5 seconds then go back up to normal idle of about 650 rpms. it does do it sometimes when warm on start up. It doesnt do it all the time though. only once in awhile. im going to replace the fuel filter tomorrow. But it has had a recent tuneup (spark plugs, plug wire, air filter, ignition coil, oil change) within the last two months. I was wondering if anyone could help me diagnose this problem. The check engine light isnt on and the OBDII shows no codes. Any help would be much apreciated. I am very mechanically inclined and know a fair amount about cars but im going to school to be a diesel mechanic so i dont know much about gas engines but what i was taught in high school.