Ford Repair: 97 expedition rough idle, mass air flow, altinator

Question
i just started havng a rough idle. sofar ive changed the mass air flow ,and also in the same week replaced the altinator. I still am having a bad idle.I just took off the idle air controll valve and cleaned it out and replaced the gasket no change.I did notice looking for a vacume leak if i hit the outside of the idle air controll valve with carb cleaner the idle picks up. do you thinnk i should replace that next???   Thanks gary

Answer
Hello and thanks for the question...I'll try to help.
 I would check to see IF the carb clean getting sucked in at the IAC valve is the ONLY place that there is a vac leak. Also, before replacing it......check the gasket....it would be more cost effective to replace a 2.00 gasket rather than a 150.00 IAC valve.
Hope this helps,
Erik