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Discussion Starter · #1 ·
So I didn't realize that that our cars had a factory wideband. I'm replacing the stock electronic gauges with a 3 gauge pod. Boost/vacuum, oil pressure, and wideband.

(I got the wideband before i knew our car had it already)

I'm going to keep it so I don't have to use an accessport to monitor it.

Now so I don't have to install another wideband can i just splice into the current one? According to the wiring diagram for a bosch lsu4.9
Green- trim resistor
White- heater negative
Orange- CDM
Not used
Red- Pump current
Black- sense
Not used
Brown- Heater positive

So I was thinking i just splice into everything except for heater +/- so its not getting power from two sources. Do you guys think it would work?
 

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No way would I splice into an O2 sensor harness. First off its a small voltage signal being returned and I would think you'd mess that up splitting it with an additional gage. And aren't O2 sensor wires something other than copper anyways? I'm no expert on the subject but I'd do some research before you tap into that harness. You might just end up with a car that runs for *&^$.
 

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Discussion Starter · #3 ·
No way would I splice into an O2 sensor harness. First off its a small voltage signal being returned and I would think you'd mess that up splitting it with an additional gage. And aren't O2 sensor wires something other than copper anyways? I'm no expert on the subject but I'd do some research before you tap into that harness. You might just end up with a car that runs for *&^$.
I was thinking instead of splitting i would make a y connector harness. Can't find any online could be a good reason for that? Haha, trial and error I suppose. If I make a y connector I could always remove it if my car runs ****ty.

I'm not sure on the material used in the wires.. is copper's melting point too low? I'm not sure..ill have to look into that.
 

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I was thinking instead of splitting i would make a y connector harness. Can't find any online could be a good reason for that? Haha, trial and error I suppose. If I make a y connector I could always remove it if my car runs ****ty.

I'm not sure on the material used in the wires.. is copper's melting point too low? I'm not sure..ill have to look into that.
I believe the wires are made of stainless steel not copper, so you couldn't just solder the connections like usual. I'd be concerned with changing the resistance in the circuit from either the gauge or whatever type of wire connections you made. I would think it would screw up the signal to the ECU and the car wouldn't run right. If it was my car i'd have another threaded bung added to the down pipe and install a separate sensor to run your gauge. But thats just my opinion. Like I said do some more research or maybe someone else will chime in here that knows more about it than me.
 

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For future reference, one does not tap the factory wideband (5V) sensor. What one does is tie into the OBD/CANBUS system to read what the sensor is doing.

Not specific to this car, but you often can't tell if the existing sensor is a fast response sensor or not. So the right thing to do, as done properly in this thread, is to use a second, dedicated sensor, put into a new bung or existing if your downpipe has provisions for a 2nd sensor.

IMO, unless you're tuning yourself, running one (without a logging function) is just adding dancing christmas lights to your car with no real benefit. Oh to be young again, and blow more than a grand on electronic greddy guages and sensors, for no reason other than I could. :p (what I did to my old WRX back in the early 2000's.)
 

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Discussion Starter · #7 ·
For future reference, one does not tap the factory wideband (5V) sensor. What one does is tie into the OBD/CANBUS system to read what the sensor is doing.

Not specific to this car, but you often can't tell if the existing sensor is a fast response sensor or not. So the right thing to do, as done properly in this thread, is to use a second, dedicated sensor, put into a new bung or existing if your downpipe has provisions for a 2nd sensor.

IMO, unless you're tuning yourself, running one (without a logging function) is just adding dancing christmas lights to your car with no real benefit. Oh to be young again, and blow more than a grand on electronic greddy guages and sensors, for no reason other than I could. :p (what I did to my old WRX back in the early 2000's.)
Yeah, i mean I truly did want it as a tuning function might end up just being flashing lights hahaha. On my truck with my Diablo trinity I have my widebands tied into the tuner to log it.

I wonder if there is a way to log my secondary wideband for a tuner to use like freektune or stratified. I know if I dyno tune it it will help..just not sure if i can tie it into the accessport logging that they use. Gotta look into it now.
 

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I believe the wires are made of stainless steel not copper, so you couldn't just solder the connections like usual. I'd be concerned with changing the resistance in the circuit from either the gauge or whatever type of wire connections you made. I would think it would screw up the signal to the ECU and the car wouldn't run right. If it was my car i'd have another threaded bung added to the down pipe and install a separate sensor to run your gauge. But thats just my opinion. Like I said do some more research or maybe someone else will chime in here that knows more about it than me.
Nah, they are copper. Just heat fabric wrapped. I have hacked into plenty enough at this point, lol

Im with you on the extra bung, I wouldnt mess with the wires to the sensor that controls a/f ratio. No beuno, not that I have any first hand experience splicing into it, the thought never crossed my mind. It could be fine, but its a bit much to gamble on.

Im about to replace my rear again, i could have sworn they are like tinned copper, I will investigate further. I am a commercial industrial electrician, and have worked with tons of different conductors/insulation types so I will give it a thorough inspection for once. It cuts like copper, SS tends to be stiffer. My money is still on it being copper.
 
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