more on idle

[TomEboi]

Hi, well I took my 2000 GT into get a "2nd opinion". Not a dealer but an independent Ford specialist. He could not find anything obviously wrong. He advised me to take it to another dealer and have them "reset my computer" or if necessary change it. It was strange cause I live in Florida and it is usually warm but this morning it was very cold and the idle actually worked better. It was very smooth and controlled but in the afternoon when it warmed up the idle was back to diving down to 500. I wonder if this is a symptom of something you guys could help me with. When the guy drove it of course it was idling fine. He told me that I should explain in detail what it was doing as he knows that sometimes it is the driver who notices things and not a computer. I plan on taking it to the person he suggested sometime next week. Thanks for everyones help. Also, I don't know if this is related but I put a KN filter in right after I got it and disconnected the negative lead on the battery all night, which was suggested on some of these boards. I wonder if that messed the computer up???? Thanks