1998 Mercury Mystique phantom acceleration

just bought a 98 mystique. 5 miles down the road the car started idling erratically and trying to accelerate while idling and in drive. I took the car back to the seller who happened to be a mechanic and he used his code scanner to tell me that the idle air intake valve was bad and needed to be replaced. No problem, so I thought. I put the new valve and gasket in and the car is having the exact same problem. Is there something else that I am missing? There were two bolts connecting the valve and one set of wires that I unplugged from the old valve and plugged back into the new one.

any advice would be much appreciated