P0420-Catalytic Converter-HELP Please
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Joined: Sep 2008
Posts: 78
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P0420-Catalytic Converter-HELP Please
I also have a post on the Vararam issue but now a different (?) issue. The issue from last week was DTCs P0171 & P0174 which was the long term fuel trim which was supposed to be corrected my moving the MAF sensor back to its original position. With the Vararam modifications it was moved next to the throttle body. Now the P0420 code is displayed. The freeze frame data is shown below:
Control Module
$10 SAE J1850 VPW
Stored Codes
P0420 Catalyst System Efficiency Below Threshold Bank 1
Control Module
$10 SAE J1850 VPW
View Freeze Frame
DTCFRZF P0420
FUELSYS1 OL-Drive
FUELSYS2 OL-Drive
LOAD_PCT(%) 2.0
ETC(¡æ) 180
SHRTFT1(%) 0.0
LONGFT1(%) 12.5
SHRTFT2(%) 0.0
LONGFT2(%) 12.5
MAP(kPa) 11.2
RPM(/min) 563
VSS(km/h) 0
MAF(g/s) 0.741
TP(%) 3.9
Control Module
$10 SAE J1850 VPW
Since DTCs Cleared
MIL Status ON
Misfire Monitor OK
Fuel System Mon OK
Comp. Component OK
Catalyst Mon OK
Htd Catalyst N/A
Evap System Mon OK
Sec Air System OK
A/C Refrig Mon N/A
Oxygen Sens Mon OK
Oxygen Sens Htr OK
EGR System N/A
Any help or ideas are greatly apprciated. Thanks!
Control Module
$10 SAE J1850 VPW
Stored Codes
P0420 Catalyst System Efficiency Below Threshold Bank 1
Control Module
$10 SAE J1850 VPW
View Freeze Frame
DTCFRZF P0420
FUELSYS1 OL-Drive
FUELSYS2 OL-Drive
LOAD_PCT(%) 2.0
ETC(¡æ) 180
SHRTFT1(%) 0.0
LONGFT1(%) 12.5
SHRTFT2(%) 0.0
LONGFT2(%) 12.5
MAP(kPa) 11.2
RPM(/min) 563
VSS(km/h) 0
MAF(g/s) 0.741
TP(%) 3.9
Control Module
$10 SAE J1850 VPW
Since DTCs Cleared
MIL Status ON
Misfire Monitor OK
Fuel System Mon OK
Comp. Component OK
Catalyst Mon OK
Htd Catalyst N/A
Evap System Mon OK
Sec Air System OK
A/C Refrig Mon N/A
Oxygen Sens Mon OK
Oxygen Sens Htr OK
EGR System N/A
Any help or ideas are greatly apprciated. Thanks!
Former Vendor
Joined: Oct 2004
Posts: 2,592
Likes: 0
From: FI Performance : Norwalk Connecticut www.FIPERFORMANCE.com
I can not comment for AZ, but we are similar in CT. When emissions plugs into us, they are looking for to see if there are any emissions related CELs and to confirm the 02 sensors are in "ready" status...
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Joined: Jun 2004
Posts: 19,459
Likes: 48
From: Schaumburg IL
CI 7-8-9-11 Veteran
St. Jude Donor '06-'10, '13
Hypertech and Predator handheld tuners will not do the trick. You need a professional tune done and edit the computer... delete out the rear 02's. You have aftermarket cats that are probably hi-flow that is the cause of the code.
