Grr. I replaced this friggin' part at least twice, maybe three times, on my '95, and now my '97 is starting to exhibit that same idle variance, where it idles normal, then sounds like it drops 100-200 rpm for 2-3 seconds, then back, then down, then back, then sometimes it catches itself at the normal place for a little while. I need to pull it off, hit it with carb cleaner, and see if I can get more life out of it, because I am SICK of spending money on that little widget.
Oh well, it'll be an excuse to rummage around under the hood and look for wiring cracks. This car is still 99M03 eligible.