Formerly known as Aldermog Member of the Inner Circle
Joined: Aug 2013
Posts: 15,794 Likes: 15 |
Peter,
you are right on open systems: but cats need to run rich to burn the CO and NOx. So with no cat the mix can be leaner, better economy.....often the lambda probe can't achieve this.
On closed loop systems with a pre and post cat probe I understand a full new map is needed so that the ECU doesn't look for any lambda probe readings.
Peter,
66, 2016 Porsche Boxster S
No longer driving Tarka, the 2014 Plus 8...
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