02 censor question
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Heel & Toe
Joined: Feb 2018
Posts: 22
Likes: 1
From: San diego California
02 censor question
I’m running kooks long tube with high flow cat x pipe, do I need to install my rear 02 censor if I’m getting it tune once my “bolt on” build is complete? Can I just plug the 02 censor holes?
thanks
thanks
Last edited by Oscarito; Feb 25, 2018 at 06:16 PM.
Race Director
Joined: Dec 2013
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So make sure that you pick up extension cables so you can plug the pre-02 sensor cables into the Pre-02 sensors on the header pipes.
The post O2 sensor connects can just be tucked up out of the way so they don't get melted by exhaust pipes, since your not going to be using these connectors.
Race Director
Joined: Dec 2013
Posts: 12,502
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The front pre O2's sensors are used for the motor when the car is running in closed loop to adjust the AFR to 14.7.
When you go to WOT, the car goes into open loop, does not use the pre-O2 sensors instead.
The Post O2 sensor are just monitoring the cats alone, and looking for a differential reading from the pre-02 sensors (are not as all to adjust the motor to 14.7AFR).
With headers, and even high flow cats after the header collectors, your moving the cats too far from the heads themselves (your heat source), so even through the high flow cats are working, they are not working as efficiently as the stock Cats when they were much closer to the head. So the post O2 sensors will not have a big enough differential reading from the Pre 02 sensors, will end up with codes (cats not working as efficiently as the stock cats).
So in the tune, the post O2 cats are turned off, which solves the problem of high flow cats not working effectually enough as the OEM cats codes being thrown.
Last edited by Dano523; Feb 26, 2018 at 02:55 PM.
