05 f150 4.6 rough idle

Recently I had to replace my battery.wouldn't stay charged. i have had a rough idle previously but not all of the time. (like a miss) now when pull up to stop sign it will lope then smooth out ( still rough idle now all of the time). it doesn't stall but makes you think it might. idle seems low. no trouble codes. Engine runs out fine with no appearant loss of power but seems to be getting worse gas milage. IAC or other problem?

How long ago did you replace the battery? It takes the computer a few miles to get it's calibration back once the battery has been disconnected. Other than that, check for a vacuum leak or a leaky PCV valve or hose. Take the IAC off and clean the inside of it with some carb cleaner then put a drop of oil on the shaft going through it.

replaced battery 1 week ago and drove over 100 miles still no difference. checked all vacuum hoses no leaks. changed PCV valve and checked hoses. nothing wrong. haven't checked IAC yet but wife scared cause i am gone out of country all the time so we traded off for new truck. Thanks for reply.

anyway warranty was out and it was paid for so everybody know what that means right?