Secondary 02 sensor for catless x pipe
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Racer
Joined: Feb 2015
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Secondary 02 sensor for catless x pipe
Just bought a set of kooks headers with off road x pipe. Just wondering what you guys do for that 02 sensor. I know you can just use the downstream 02 sensor already on the car, but I don't want it just dangling there. I would also rather not cut it. Do you guys just tuck it away somewhere or is here a plug/bolt I can use?
Race Director
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From: Raleigh, NC
St. Jude Donor '15
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Rear O2 ports get pluged in the X pipe, the rear O2's sensors get unplugged from the cables/cables tied up out of the way, and the rear O2 sensors get turned off in the tune.
Hence without a working cat, there will not be enough of a differential reading between the pre and post O2 sensors, and with both in play, will end up throwing codes.
Hell, even with high flow cats since they are less effective than the OEM cats, the rear O2's still get pulled and turned off in the tune.
Really, all the rear O2's are doing it telling the ECM how effective the cat's are preforming only. So the ECM is using the pre O2's for the needed adjustments, and the rear/post O2"s are just checking to make sure that the cats are doing there job to reduce the emissions more.
Hence without a working cat, there will not be enough of a differential reading between the pre and post O2 sensors, and with both in play, will end up throwing codes.
Hell, even with high flow cats since they are less effective than the OEM cats, the rear O2's still get pulled and turned off in the tune.
Really, all the rear O2's are doing it telling the ECM how effective the cat's are preforming only. So the ECM is using the pre O2's for the needed adjustments, and the rear/post O2"s are just checking to make sure that the cats are doing there job to reduce the emissions more.
Melting Slicks
Joined: Dec 2013
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From: Bridgewater New Jersey
Last edited by extrapilot; Dec 19, 2015 at 05:10 PM.
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Joined: May 2004
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From: Raleigh, NC
St. Jude Donor '15
You are absolutely right, sorry about that.
Thread Starter
Racer
Joined: Feb 2015
Posts: 274
Likes: 9
Thanks guys, just ordered two of these. 3.50 each. I figure it will be a lot neater to just plug the hole with those rather than have to tuck the sensor wires out of the way.
http://www.summitracing.com/parts/vp...FUSPHwodNk4JRw
http://www.summitracing.com/parts/vp...FUSPHwodNk4JRw
