Yes, I was able to replicate the situation while parked with the engine
running. It seems that when I take my foot off of the accelerator, the
engine idles very low, and then back up to where it should be. When the
idle goes very low, I can feel the car slightly vibrate, like it was
thinking about stalling, but changed its' mind.

I'll check my battery. If anything that I just said in this entry helps
you determine my problem more, PLEASE share that with me. I appreciate all
of the help so far.
Thanks.