EFIE module. I found a write-up a guy did on this device. He calls it an Electronic Mixture Controller. He has the complete schematic and diagrams as well as parts list for the device. I found that the voltage shift is very tiny. Basically when the O2 Sensor says there is X amount of Oxygen in the exhaust the device changes the signal by a fraction of a volt to lower that number by a definable amount. So you can tell the ECU to lean out a hair. If you pair this up with a handy dandy mixture gage from JC Whitney you can see what your engine is really doing. The plans I received build a device with a fail safe by=pas switch that turns it back to normal with just a single switch to bypass the whole thing. I like the design and I am going to construct it soon.

I now have almost all of the parts for the electrolyzer in hand. I will start construction this weekend. I surmise with my schedule it will be a few weeks before I have stage 1 built. I will post pictures and full results. Our goal s to get from 16MPG to 19.5MPG with the first stage. ~20% Gain.