Symptoms of too much Water Injection

[JohnA]

Originally Posted by Slump

This is a dyno of my car.

The blue line is "too much water", and the red line is a more correct amount of water.

The only difference between the two dyno runs is the adjustment of the quantity of water injected using the Aquamist MF2 controller (part of the System 2S).

Interestingly, the blue 'drowning' run also appears to be much richer in fuel.
Did the extra water fool the oxygen sensor, or did you also change the fuelling as well?