MSefi.com read only forum (Jan.15,2018)

I am converting a previous EFI project to use a MS2 controller. The car was set up with the EZ EFI multiport system which uses a five wire O2 sensor. The wires are red, black, white, gray, and yellow. I am having a hard time finding the proper wiring diagram for this. I'm not sure if this is really going to work, after looking at the operation of the five wire sensor on youtube. Would it be better to switch to a Bosch type four wire unit? Just as a note, the EZ EFI is not very capable. I would not recommend it.

That would be a wideband O2 sensor. While most sensors give a simple resistance or voltage based output, wideband oxygen sensors are different. The Bosch LSU sensor combines a Nerst cell (like a narrow band oxygen sensor) combined with an oxygen pump that extracts oxygen from the exhaust to determine the actual air-fuel ratio. It requires a control circuit to drive the pump, and none of its outputs are anything you can plug into a simple analog-to-digital converter and get a reading you can convert to oxygen levels. So a wideband oxygen sensor requires a dedicated controller circuit. As this circuit is not built into Megasquirt, you will need an external control device like an Innovate LC-2 to convert its output into a signal that Megasquirt can read.