P0420 - Catalyst System Efficiency Below Treshold (Bank 1)

mrnewt · Post by **mrnewt** » Tue Feb 16, 2010 8:17 am

Hi there,

Recently I have upgraded to Vibrant headers with high flow cat and retuned the ECU to the mass flow setup - "AEM SRI, race header, hight flow cat, stock catback". (I do have a Magnaflow catback, but there is no option for AEM SRI, headers and catback).

Anyway, after 200-300 km check engine was on with the "P0420 - Catalyst System Efficiency Below Treshold (Bank 1)" error.
Ecu code: 37820-RRB-A07 -- 4743-104240

Any ideea why this migth happen? And how could I take care of it?
I have uploaded the calibration used and one the most recent datalog.

Thanks!

all-black · Post by **all-black** » Tue Feb 16, 2010 11:51 am

disable the secondary o2 sensor in flash pro or use a defouler

mrnewt · Post by **mrnewt** » Tue Feb 16, 2010 11:56 am

nm ... found it (speed density setup only!?)

mrnewt · Post by **mrnewt** » Thu Mar 18, 2010 9:35 am

Ummm ... is there any chance I could disable the O2 sensor on a "Mass flow" calibration? I don't seem to have the option in the "Closed loop".

For whatever reasons, when I have the FG2/FA5, AEM SRI, race header, highflow cat, stock catback setup, I get the check engine light and same error.

Is this a case of ... use defouler?

Post by **Spunkster** » Thu Mar 18, 2010 9:52 am

No the secondary is not able to be disabled in a AFM calibration, only MAP based calibrations.