You just replied to an 8 year old post........

 

LOL yes i did

 

I know this is an old thread, but just checking to see if your issue was ever resolved. I've had similar problems for the past month. Replaced air filter, removed Throttle Body and cleaned, cleaned MAS with no improvements. No issues with a short 5-10 min drive, but any longer and it will stall out occasionally when RPM drops and idles very rough, like its missing. If I press on gas while in idle RPM bumps up to 1600 for 45seconds or so then drops back down to 550, idles rough and wants to die. I have to put it in park at stoplight and rev up to keep from stalling out.
Took to local mechanic, he plugged it into computer and said the fuel trim settings were off. Possibly related to a Flex Fuel sensor telling engine that I was using E 85 fuel when I'm not and causing it to run super rich. He adjusted some settings and it's driven fine for about 4 days, but last night the same stalling and rough idle issue returned.
Seems like other folks have same problem, has anyone ever traced it to a bad flex fuel sensor...is he on the right track? I have to have it replaced or it that's not the issue.
Thanks

 

The shop saw the problem of fuel trim tables shifted.
Why did he not check it out, but just guessed? That's why you still have the issue.
He cannot make any 'adjustments'.
Did you get taken or was the shop incompetent?
.
The intake system has a vacuum leak that has to be found and fixed.

The shifted tables makes the fuel too rich, causing rough idle and stalling after the engine come up to temperature, and fuel mileage will also suffer.
There is no mystery to this. Correct the fuel trim tables and it will be good again.
If left as is, what happens is a code clear or reboot of the computer will return the tables to normal and run fine until they shift again from the vacuum leak, then return to rough running and stalling again.

Good luck..

 

yeah man change your plugs but do it yourself with the ford form sparg plug remover