Ok. I have done everything here except the Throttle body. Runs better, but not good. Low rpms really rough. Once (sitting still) I get it up to about 2000 rpms she smooths out and I can hold her there (or higher) but won't hold well at 1500 or below. Drove her down the street and can't get her up to high enough rpm to run smooth. Rough. Better than before, but something still wrong. Thoughts?
Did you run seafoam thru the vaccume (brake booster) tube?
Did you check the air filter condition?
Did you hit the MAF with MAF cleaner?
You could change the fuel filter. (if not done recently)
Do a search in here on the 90deg. elbow vacuum leak & check it..
Start the motor and spray carb cleaner all over around / in back / under (all over) the throttle body area. Listen for the motor to change it's idle (this will tell you the area of a leak, should you have one)
I would seriously recommend getting a cheap code reader $60.00 at Oreilly's Innova one works great...
Clear the computer, disconnect battery for 15 minutes or so? & then run the ODB2 Ford drive cycle...
http://www.obdii.com/drivecycleford.html ... The code reader is handy to have hooked up when running these tests because each 'test set' is displayed on the screen, as you do the drive cycle, each test that is run successfuly will drop off the readout...
When you've run all the tests (don't worry about the evap test, it won't run right away) take it into a parts shop & have the computer read for codes? if you decide to not buy a reader.
Make sure you run the misfire test... I'm interested in that test to eliminate plugs / cop issues..??
Lastly, the IAC 'could' be shot (doubtful, but possible) it's a cheap part but save it for later...
That's all I got right this minute...