Well, new plugs, cleaned MAF sensor, cleaned ICM and still the misfire, or should I say 'hesitation'. Took the car to a fella I trust who has a Snap-on ECU code reader; the read-out was 'Solenoid B' error and 'Trans Temp out of range' error. He said that he didn't really know for sure but that the tranny may be trying to shift, but can't, and that is causing the engine to run rough. I remind you all that while the engine is cold the engine runs smoth, it only occurs after the engine reaches operating temp. Also, the rough running is intermittent, sometimes it does it and sometimes it doesn't. The plugs that I removed showed no signs of rich/lean running; healthy.

Appreciate and and all ideas.

how old are the wires? did he look at fuel trims? im not figuring how a trans temp error would cause a mis or hesitation unless it was the converter trying to lock or something

Hi Justin, are you implying that the solenoid b error problem could not cause a mis or hesitation? I have only the word of a non certified mechanic that it could. And yes, I think the wires need to be replaced but I thought I would wait because I didn't think the wires would only short when the engine was up to temp; am I wrong?

old wires do get worse with heat but its not normally so random like one moment bad the next fine, unless there is a spot thats loose and leaking current out when it gets near a bracket for example

try starting the engine and misting the wires with water and listen for the engine to change pitch

Something strange is happening! Yesterday, I ran around town, just 3 or 4 miles and the engine ran perfectly Today my wife drove the car to work and back home, 28 miles, with out any problems. This is the first day that she has taken the car to work in 3 months without a problem. I hate when things like this happen!!! The day I worked on the car it, on the test drive it ran bad, 3 or 4 miles. Now it runs just fine! Why??? Now I wait for the proverbial other shoe to drop.
I am going to put new wires on next Thurs; probably will start running bad again!

see if the wires are coming close to something

What are the best wires to buy?

hard to say, i used to buy delphi mostly but seems like they arent vary good lately either, most are made in china these days i think. i have been buying the second level store brand lately, seems to run ok and if i have a problem i can take it back easy.

Just an odd thing I had happen: A dying Battery that after engine warm up would cause a random hesitation, miss fire or even engine shut off. Battery tested "good" yet it was 7 years old. On a hunch I swapped it and the issues went away.

Intermittent loss of ground, or power wire grounding can do the same things.

I used the NGK set ..for my Park Ave- perfect length and fit.

I think the NGK wires perform well, quality boots, and Blue was a good match!