98 F-150 Wont Idle When Cold

Have A 98 F-150 4.6l And The Truck Has A Hard Time Idleing
By Itself When It Is Cold Outside.when You First Start It Up
You Have To Feather The Gas Pedal To Get It To Idle.after
5 Min Of This The Fast Idle Kicks In And It Will Idle Alright
No Codes Come Up

Thanks Guys

Just a shot in the dark but I would suggest changing the TPS and the Idle air control sensor I have a 89 with a 300-6cyl and it was doing the same thing so I changed both of those and a good tune up and it cleared right up.