Just disreguard this if you don't have a 5.4 Liter.
If You do, The IAC is the the part circled (apparently) It's about $40 to replace at almost any automotive store (Discount, Autozone etc.) Or You could clean the sensors (After Unbolting) With Electrical Contact Cleaner...
It's due from a prolonged build up of carbon dust coming from your Engine, therefore if cleaned, it will only last you so long.
Hope this helped in any way possible... Peace