Originally posted by warmonger:

The electrical ones preserve the shape of the signal oscillation but just drop the voltage and amplitude of the waves.

For as good as they are, I think that soldering a 1uF cap in parallel with the sensor signal wires and a 1 megaOhm resistor in series with the signal wire is very easy.



I believe the circuit changes the shape of the O2 sensor output. It's basically a low pass filter so a square wave input will come out as a rounded off triangle wave albeit lower amplitude and less peak-to-peak. This fools the computer to think the O2 is working correctly.

BTW, I've confirmed that lighting MIL does not enrichen the fuel/air ratio. The blinking MIL however is another story.