02 Sensor Help

LawDBrowning

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Can anyone help me diagnose this?

I have BBK Longtube Headers on my 2011 3.7L V6.

My Upstream 02 Sensors are constantly fluctuating to the negatives which means the voltage is all messed up but I have brand new BBK Extension Wires and brand new NTK 02 Sensors. The car runs not great because of it and my 0-60 is literally 13 seconds right now.

When I remove the extensions and 02 Sensors to plug them into the factory harness by the engine (just to leave the Sensors hanging for a second for diagnosis) the Sensors read positive all the way around again. That means it pinpoints to the Extensions being bad or faulty. But how when they are brand new? This is the second pair of Extensions I have tried and I am still getting negative readings. I am ready to take it to a Ford Dealership for a proper solution.
 

DieHarder

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Are you sure you have them plugged into the proper locations? We've seen several instances where owners have made mistakes.

https://www.s197forum.com/threads/roush-stage-3-running-lean.135583/#post-2440174 - "Reading this reminds me of the classical mistake made when reconnecting O2 sensors after a clutch job, or LT's or OR pipe mod is done. The O2 sensors get connected backwards. Causes one side to go lean and the other side to go rich. May wish to first check this as you have no idea what the previous owner did to the car prior to selling it."

https://www.s197forum.com/threads/corrupt-base-tune.129551/#post-2346498 - "It has happened many times to the best, but you can get the sensors crossed when reconnecting them. This may be the cause for your 2196,2198 codes. Recheck and recheck. There are manuals on this site that will show you proper routing on the O2 sensors. You may wish to google O2 sensor connections as well. I know this sounds crazy but even the guys at Brenspeed admitted to making this mistake on occasion...that is how simple it can be to cross them."
 

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