anyone else have a surging idle in park or drive? or a high idle after initial high idle on a cold start?

both my moms 03 xploder sport and sarahs have the same issues...just wondering who else is experiencing this.

dealer replaced the IAC on my moms and its worse now then before...

i refuse to work on warrentied vehicles unless its maitence or i'd DIM...

 

my idle has been weird lately to
Usualy when i start it up after it has been sitting for awhile the rpm's are high for a few seconds..around 1,500 rpm's, then they drop to 1,000 or less (normal for ALL vehicles)

Lately when i start it up after sitting for a long time the rpm's do NOT jump up. it goes right to 900rpm's and stayes there.
i dont no what is happining because it should start high then drop low.

 

usually vehicles idle around 600-750 rpm, my moms idles at 1,000 rpm average. her idle doesnt surge as much as sarahs but its strange it happens on both...

sarahs has more of a surging idle, like it has a lopey cam. it idles a little high...say 150 rpm...

my moms idles high, more so after ford "replaced" the IAC because the "valve was knicked"...hers surges a bit as well.

 

Does it go away or get better the more the engine warms up???

 

mine kind jumps every 2 minutes if it's in P or N. goes from like 700 ro 1100 like I tapped the gas or something and then it's back fine. I've had a problem before that it was idling at like 200 then it would die. The guy at Ford fixed it and it idles fine now, not sure what the problem was though.

 

My '01 does a similar thing as it drops to 500 and surges then dies and gets worse the longer it runs