986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - Help with explaining headers @ o2 sencors 2003 boxster

Gelbster · 05-10-2017, 08:20 AM

First understand that the SMog authorities will castrate you for doing this.It will fail any Visual Test by a Referee. But let's assume you are at peace with that.
It is possible to fit a (new) set of O2 sensors(all 4) using the bungs in your new headers. The rear positions require "extenders" to cheat the system into thinking all is well.
To fit the Bank 1 extender you need to cut a large piece out of a redundant web on the crankcase.
Not pretty or legal, but it should work to extinguish the CEL and you may pass the Smog Test.YEMV.
Please let us know if this works?
What happened to the old Cats? If they are still in good condition they have some value.

05-10-2017, 08:20 AM	#3
Gelbster Registered User Join Date: May 2014 Location: S.California Posts: 2,027	First understand that the SMog authorities will castrate you for doing this.It will fail any Visual Test by a Referee. But let's assume you are at peace with that. It is possible to fit a (new) set of O2 sensors(all 4) using the bungs in your new headers. The rear positions require "extenders" to cheat the system into thinking all is well. To fit the Bank 1 extender you need to cut a large piece out of a redundant web on the crankcase. Not pretty or legal, but it should work to extinguish the CEL and you may pass the Smog Test.YEMV. Please let us know if this works? What happened to the old Cats? If they are still in good condition they have some value.