I've been reading all the oxygen sensor posts for the past 2 hours and not sure how to proceed. I have the P0138 code, 02 circuit high voltage bank 1 sensor 2. I just got done with the Hughes kit plenum repair along with new plugs, wires, cap and rotor along with a few other minor repairs. I also got the NTK downstream 02 sensor when I ordered the Hughes kit. The problem is that the NTK sensor has the square connector, but I have the round connector on the truck. The only round connector I can find is the Bosch which an overwhelming majority of people seem to have problems with.

I thought I saw somewhere that someone used a NTK 23099, but that shows as not being a fit for my 2001 5.2l. I saw one post where the person disassembled the connector to make it work but I don't see a way to get my truck's connector apart. Can anyone help me out with how to proceed?

 

Take the one you have down to your local auto parts store, and see if they will swap it for a sensor with the correct connector. Either that, or, return it to where you got it from...... see if they will send you the correct sensor.

 

https://www.rockauto.com/en/moreinfo...366589&jsn=465

 

This part does not come up when I search for my specific vehicle. Does that not matter? I also went to the NTK website and they only showed 1 for my specific vehicle.

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If you go to Rock Auto and search your vehicle, you will find it. The first one listed has the square plug. This one was the 2nd or 3rd NTK listed IIRC.

 

What is the problem with Bosch O2 sensors?

 

Our trucks just don't like them. They are slower to react, so they tend to confuse the PCM, more than let it know what's going on.

 

i think i might have replaced my 02 sensors with bosch (got them from autozone), its been a couple years. Could they be part of the reason i get horrible gas mileage? On start up, my exhaust smells really rich. It goes away after the truck is warmed up.

 

Entirely possible. I would check the coolant temp sensor as well.

 

Ill change it out and possible the o2 sensors as well.