I have 4 wires on my 02 sensor. 2 white, 1 gray, 1 black. Im hooking up a/f gauge and i need to know which wire i need to hook up to it. does anyone have a diagram?


also i have a fuel pressure gauge that needs to me installed, they game me a fuel pressure unit with a 1/8 thread, where would this fit and get acurate fuel pressure readings?