2002 Taurus Duratec engine miss

I have a 2002 Taurus that has developed a miss. It's a 3.8 Duratec with 70,000 miles. At idle you can feel the miss very slightly (about 1 miss every 10-30 seconds, not steady), but when you turn the AC on you can feel
the miss allot more. Also going up a hill at low RPM's, very sluggish. But the strange part is that it does not do it all the time. I have not been able to determine exactly when it does it and when it doesn't. Very frustrating....
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wrote:

lighty mist wires that will find the culpret
hurc ast
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I tried the mist test which showed nothing. I then replaced the spark plug wires and it took care of the miss, for about a month. Now the miss is back????? It is REALLY noticeable when the air conditioning is on. HELP !!!
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plug
Is the check engine light on? If so, did you have the codes checked? This should tell you which cylinder is missing.
Did you replace the plugs? How many miles on the engine? Any moddifications?
Ed
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