I am hooking a heated oxygen sensor up and have everything figured out, hopefully; but have one question. Is the tan and white wire that goes to the relays on the firewall all right to hook the positive wire to for the heater on the oxygen sensor???According to a wiring diagram that wire is for the fuel pump signal. I was going to hook it up to the orange wire but apparently that is hot all the time. I believe this tan and white wire is only hot when the fuel pump is actually running either by the oil switch or relay.

 

I'm lousy with wire colors, but I think the fat orange wire on one end of the fuel pump harness plug is the ignition hot. You can (and should) easily verify this with a digital multimeter. You can use a test light too, but stay the hell away from the little green wire in the fuel pump plug. If you try to check that wire with a test light, or if you have a lapse in judgement and try to run the heating element for the o2 sensor off of that wire, you'll fry the output transistor in the computer. Ask me how I know that.

 

Or you can try it this way:

 

So which wire would you hook it up too? Apparently the orange wire is hot all the time. Is that right?

 

No, the orange wire is just hot when the ignition is on. Vader's diagram verifies that, but like I said above, you should NEVER hook stuff like this up without first verifying first-hand with a digital multimeter.