Eddie 70

Quick question about how to wire up the O2 sensors. This is in my 70 LS swap. I am putting rear O2 sensors in my front locations. I want to be sure I have everything setup correctly.

Which wires are what on the rear corvette O2 sensors? I know one of the wires is a sensor wire, one has 12 volts on it and one has to be ground. I need to know which wire is what on these sensors.

Thanks for any help.

Patches

Eddie 70

Thanks Patches that helps some. Looks like the new Bosch 13111 sensors are a little different to me.

On my harness, it came from a camaro, has only slightly different colors in the plugs.

Passengers side plug.
A=Tan
B=Purple
C= Black
D=Pink

Driver side plug
A=Tan
B=Purlple/white
C=Black
D=Pink

A and B are sensor. C is ground and D is voltage. All good so far.

The Bosch 13111's are like this.
A=Grey
B=Black
C=White
D=White

Looks to me like the white wires are the sensor wires on the O2's. The black should be ground and the grey should be 12 volts.

If this is so, then plugging the 13111's into my harness is not going to make them work. Agree?

I wonder if it is possible to repin the O2's to match the harness?

Patches

Agree they won't work as is but repinning should resolve that.

Obvious Question #1: Why not use OE O2 sensors since your harness is stock?

Eddie 70

This is a conversion car. I have put an 02 Camaro SS LS1 and harness into my 70 vette. It has headers. I was reading and everyone with headers is using rear O2 sensors because they have a better heating element in them and should keep the slow switching codes at bay.

For some reason, I thought since I was putting a new motor in I should get a cam, headers, heads, etc... just so it would sound nice and mean. I got that for sure.

If I could have just left well enough alone and dropped the stock LS motor in there and enjoyed it, I would be wanting to do something else to it. I will get it though. I do have HP Tuners and am not afraid to do anything to this car. I have touched every nut and bolt at least once on it. The only thing I have not done myself is the paint.

Eddie 70

Now I am wondering, since this is a Camaro harness, are the pins layed out differently?

Patches

These are for the 02 Camaro.

Eddie 70

Those colors match what I am seeing in my harness. C and D are the heater as I thought.

What confuses me is both sensors will read to the O2 on the A terminal.

I plugged them in as they are and left the key on and watched the display on HP Tuners. The voltage on both stayed very similar. I slid under the car and you could feel them both getting warm.

I am still not sure I understand the wiring.

Just for comparison, I did look at an old Delco O2 sensor and the colors were
A=Tan
B=Purple
C=Brown
D=Brown

Patches

Sounds like the Bosch are wired similarly. No schematic came with them? If the sensors are warming, and you are getting a correct output to HPT, they must be the same.

Eddie 70

Thanks for your help.

I have one more question for you, where are you coming up with your diagrams? Do you have this on a disc? Is this the one I see every now and then for sale in the C5 section? If so I need to pick me one of those up.