Why after doing a spark plug change will my car idle at 1000rpm on 1996 Ford Taurus

Car idles smooth but fast then when you increase acceleration when it gets to around 3000rpm its like it either flooding or starving for fuel and just about stalls..previous to the spark plugs being done it had a nasty little miss but could not be picked up as it did not throw a code..................

by in Milton, NH on February 03, 2012
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1 answer 1 comment
ANSWER by , February 04, 2012
Clean your MAF sensor and air intake control motor, perhaps throttlebody as well, and see if fast idle clears up. The miss you notice could be a coil going bad and it won't throw a code till its worse or completetly gone.
COMMENT by , February 10, 2012
Hi thanks for that did that plus changed the leads as i noticed the rear spark plug leads were a different make and looked a lot older...ok now it purrs like a cat trouble is at 1200rpm if i remove the lead to the iac it returns to normal revs if i turn the a/c on it increases revs as expected turn the a/c of back to 1200rpm...put it in gear idles normal...put the lead back on the iac 1200rpm ...also sometimes if i increase the revs in idle to 2500-3000rpm it shudders and hesitates then as the car warms it is ok and will rev to 4000rpm without a problem but then agin to 1200rpm idle...could the iac valve or egr be stuffed both items are original....Thanks