> >I noticed my mixture bar was going from lean to totally  
> desapearing. Turning the knob to full rich was not enough.
> I saw this a few times.

Buly;

It would be interesting to know if you had it previously tuned giving you
correct mixture.  I have had on-going problems with spurious changes to
settings in the EC2.  Carefully tune it one day, and find things have
changed the next, and have had tuning changes occur during flight.  I have
noted changes in the mixture table, stage point setting, injector pulse
width. Many, many hours spent trying to determine cause, but as yet no
explanation.  It has been assumed that it is specific to my installation -
composite pusher with EC control box at the firewall, EM2 acquisition module
at the firewall, display on the panel.  The problem is primarily with
controller A which communicates with the EM2.

This may not be relevant to your installation, but it would be worth paying
close attention to getting it tuned correctly, and see if it stays that way.

Al