V6 warm idle problem

[Matt Danning <mdanning@domain.elided>]

My 87 Milano idles fine when the engine is cold.  When it warms up,
though, the idle gets lumpy, and it misses and surges slightly.
Spark plugs are new and properly gapped, wires were replaced by PO usinf

factory wires, cap and rotor are new, o-ring in idle air bypass is new.
Does anybody have any suggestions about where to look next?  Thanks,
Matt

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