So I have a 91 hatch with a b16 and I didn't pass emisions (in Chicago). So I decided to install my vafc now instead of with the turbo. The question is what the hell is the vtm wire ( blue wire) for. Also, will doing the blue wire mod give a cel or make the vafc not work correctly. The wiring diagram from apex website didn't say to use it for my car/motor but it also didn't get one of the wires right.
Thanks for the help kids.

 

From what i can remember the blue wire (in the case of honda's) can be used as an auxilary input which you can connect to the O2 sensor. This way you can monitor the O2 sensor voltage. It won't tell you if its running lean or rich untill you calculate what the voltage reading actually equates to.

HTH

 

sort of a a/f gauge mod