I am trying to discover the exact method of hooking up my electric sending units to EFILive through my unused rear O2 sensor connections. Have you guys that have done this just chopped the connecter off of the sensors and ran the signal wires in down underneath, or have you tapped in under the hood?

 

secret



let me look for the post i had awhile back, it has resistor values and stuff. i put the wires under the truck and tied into the wires down there. i used 2 old o2 sensors i had and cut off the sensor and hooked onto that.

 

this will help a little, if you are using the same sensors as me i can give you the formula for the pid's too. https://ls1tech.com/forums/showthrea...t+fuel+presure

 

this is what i used for the boost formula ({GM.LS1.O2S 22} -450)/30.75
this is what i used for the fuel presure formula, let me know if you figure out a way to smooth it out a little ({GM.LS1.O2S 12} -460)/4.21

 

Yea, I had found that post, but it didnt really speak as to how you did it... I have the autometer electric boost and fuel pressure guages.

I was planning on just cutting off the old sensor plugs and capping off the wires I dont need. I looked at the truck wiring schematics, but I am stupid!

 

Did you put the resister in series with the signal going to the pcm from the sending units? Is it the same resister for both gauges?

 

same resistor for both, i came off the autometer sensor wire to a resistor, then from the other side of that resistor to a wire that ran to the rear o2 input wire.

 

I can't seem to get signal to the pcm... I'm coming off of the white autometer signal wire from the pressure sensor at the fuel rail to a resister and then to the O2 input... Is this a one wire scenerio, or did you have to do another ground?

 

just one wire. put a volt meter on the sensor and see if you have voltage there. then check the other side of the resistor and see what you have there. it should be 0-5v on the sensor and then 0-1volt after the resistor. last thing is be sure you are hiting the correct wire on the o2 input. i cant remember what wire it was. seems like i used my ohm meter to check voltage to ground and when i checked one of them i could see the signal jump on efilive. thats how i knew wich one it was.