ok, my baby is being weired on me latley, sometimes she will idle perfect, but yet sometimes she will be idling funny, the needle is jumping around alot on the rpm gauge, and u can hear it, and once ina while she dies out, but sometimes she runs perfect, i need some help, its basicly stock except for a air filter

 

Here are a few things to check. Check the MAF, IAT, IAC senors, or have a shop do if for you, you may also want to get the thermostat and alternator checked as well.

 

Clean the IAC... heres a link to solving idle problems....

http://www.muscularmustangs.com/maintain.php