2006 Ford Taurus misfire/ECU question

I have an intermittent problem at startup with my 2006 Ford Taurus. First of all, sometimes it throws a “misfire detected in first 1,000 revolutions” error code. The HT leads and ignition coil pack have been replaced, but I still occasionally have the same problem.

Now, I’m beginning to think that the first problem is related to the second: Every once in a while when I start it, the RPM and speed gauges try to go BACKWARDS. I have to shut off the engine, wait for the needles to stop rattling against the stop post, and re-start the engine.

My first thought is that the ECU may be intermittently shorting or it’s starting to go bad, and needs to be replaced. Has anyone else had a similar problem?