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MNBoxster · 11-21-2006, 09:42 PM

Hi,

The spacing of the O² Sensor Bungs is critical because the DME attempts to sample the same exhaust pulse both pre and post catalyst for proper Fuel/Spark Map selection.

If the same spacing is not maintained in an Aftermarket Header/Cat combination, the sampling won't be from the identical cylinder and the DME will not be able to make the proper selection and poor performance and/or poor running could result in addition to a CEL.

One of the 1st Aftermarket Headers (I don't remember if it was Fabspeed, B&B or some other brand) had an issue with this until they properly spaced the bungs. Hope this helps...

Happy Motoring!... Jim'99

11-21-2006, 09:42 PM	#5
MNBoxster Registered User Join Date: Sep 2005 Location: Minneapolis/St. Paul, Minnesota, USA Posts: 3,308	Hi, The spacing of the O² Sensor Bungs is critical because the DME attempts to sample the same exhaust pulse both pre and post catalyst for proper Fuel/Spark Map selection. If the same spacing is not maintained in an Aftermarket Header/Cat combination, the sampling won't be from the identical cylinder and the DME will not be able to make the proper selection and poor performance and/or poor running could result in addition to a CEL. One of the 1st Aftermarket Headers (I don't remember if it was Fabspeed, B&B or some other brand) had an issue with this until they properly spaced the bungs. Hope this helps... Happy Motoring!... Jim'99 Last edited by MNBoxster; 11-22-2006 at 06:03 AM.