93 Cutlass very rough idle

Hello,

My 93 cutlass 232000 miles 3.3 litre suddenly began surging and bucking at low speeds and has a very rough idle when it is in gear. The engine misfires and will not run smooth. At higher RPMs this is less noticeable. Swapped out the coil packs, changed the plugs and wires but no luck. At idle it is almost as if a sparkplug is not connected, but they are all firing I confirmed with a timing light.
Any thoughts would be appreciated.

Thanks to all who viewed this post.. Turns out one of my new wires was a dud.. I realized this when I was rechecking the plug connections and the wire pulled right out of the housing..cheap wires serves me right but I will not be keeping this car much longer. Popped one of the old ones in place and it is smooth as silk.

This forum is a very valuable resource which I turn to only when I am totally stumped. Thanks again for your time!

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