O2 Sensor Issues

[Qball]

I'm not sure if this is the right place to ask this but I need some help. I recently put the exhaust on from my old k1500 on to my new k1500 same year different engines old was 5.7 new is the 5.0 so same block. The issue is that the downstream 02 sensor on the exhaust for bank 1 was farther down so I just tried splicing in some wire and got dtc code P0137. Didn't matter if I soldered it or used butt connectors it still threw that code so I got a universal O2 sensor and used everything provided with it to splice in the OEM connector and still get P0137. So my question is could the extra 4-7 inches of wire really be causing enough of a voltage drop to throw the code I wouldn't think it'd make much of a difference but maybe someone here can help because I'm out of ideas other than trying to splice wire into the connector on the truck. Any help is appreciated

 

[SUBURBAN5]

Was battery connected?

 

[SUBURBAN5]

Nvm after reading the code I doubt that would make a difference.

 

[delta_p]

Did you clear out the code and it came back after the resplice?

 

[Qball]

Did you clear out the code and it came back after the resplice?

Yes I did

 

[delta_p]

Did you confirm the wiring when splicing. tan is sensor low, purple is sensor high, pink is heater supply, and black is ground. There can't be any short between tan and purple or it'll throw that code.

 

[delta_p]

No exhaust leaks too, that would cause a lean condition that might throw the code.

 

[Qball]

No exhaust leaks too, that would cause a lean condition that might throw the code.

Im fairly sure that's there no leaks or at most a small one. As far as wires goI had different colors on mine I had two brown a grey and a tan/ light brown. According to the table I got with the universal sensor grey is signal wire and tan is ground and I matched those ones up to the corresponding wires on the sensor

Edit: There was one potential leak at a flange not far behind the O2 sensor but I used some exhaust putty and fairly sure I've got a decent seal there now. Yes I know could get an actual gasket but trying to remove the flanged rounded one nut and I'm fairly sure the others would snap and I don't wanna go through the process of replacing the studs as it seems like it would be a pain to do off a lift, just using a jack and creeper

 

[Erik the Awful]

Did you include the ground strap when you swapped the exhaust over?

 

[Qball]

Did you include the ground strap when you swapped the exhaust over?

I dont recall there being a ground strap on either of them