water injection questions

[George M. Dailey]

At 08:38 PM 7/21/96 -0700, you wrote:
...this unit is controlled by an adjustable "O.E" quality pressure switch, for
>turbo engine use, so some other means of turning it on would have to be used
>on non-turbo cars.  A 4-gallon aluminum reservoir is shown on the catalog page.
>
>A lot of people mix Methanol (50/50) with the water.  Water alone will act
>to slow the combustion process; equivalent to raising the Octane rating (All
>Octane rating is, is a gauge of how fast a particular gasoline fuel burns in
>a combustion chamber).  The ignition timing can then be CAREFULLY advanced
>to take advantage of this.  With Methanol, you have a more pronounced effect
>(The equivalent Octane rating for Methanol is 105).
>
>If anybody tries this, be extremely careful.  If you forget to keep the tank
>filled and you don't have sophisticated controls to either tell you of this
>or to shut the advance curve down to stock when there is no injection taking
>place, you will cause yourself a problem....
>

How would GM EST react to this situation? On my 89 TPI set up, I noticed
that after running high octane fuel for a week and then switching to the
cheap stuff, if I floored the throttle I would hear a few detonations and
the check engine light would come on. Code 43 EST. After two or three times
of this, it would start working normally. Does it take the ECM this long to
adjust.

GMD