Code po420
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Joined: Dec 2005
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From: NEDERLAND TEXAS
Code po420
I'm ocasionally getting a code PO420 catalyst system efficiency below threshold [ bank 1 ]. 2007 Z06 with ported throttle body from V-MAX & ATTACK BLUE FILTER from TKO PERFORMANCE.I take short trips to work,5.5 miles,and mostly around town driving. Any ideas????????
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Joined: Aug 2004
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From: ★ Performance Parts & Accessories ★ 1800 778 9898
St. Jude Donor '07-'08-'11-'12-'13-'14-'15-'16-'17
Headers, high flow cats? Possibly o2 sensors.
If stock with high miles it could be a cat on the way out...
If stock with high miles it could be a cat on the way out...
Burning Brakes
Joined: May 2006
Posts: 1,171
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From: foley al
it may be bank 1 cat or cat monitor(rear o2 bank 1,bank 1 is the side with cylinder 1) if you could monitor pids for o2 sensors for one side, bad cats will show up as having a simular signal for front and rear 02 sensor reading(a wave going rich to lean,where the rear sensor reading should be linear) usually cats are covered 8 years,80,000 miles
Drifting
Joined: Sep 2009
Posts: 1,719
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From: cinnaminson n.j.
St. Jude Donor '14
Your car probably needs to be reflashed by the dealer under warranty. see TSB below
TECHNICAL
Bulletin No.: 09-06-04-011A
Date: April 03, 2009
Subject:
Malfunction Indicator Lamp (MIL) Illuminated, DTCs P0420 and/or P0430 Set (Reprogram Engine Control Module (ECM))
Models:
2007-2008 Chevrolet Corvette ZO6
2009 Chevrolet Corvette ZO6 Built Prior to VIN Breakpoint 95112736
with 7.0L Engine - RPO LS7
Please Refer to GMVIS
Supercede:
This bulletin is being revised to update the reprogramming emission controller warranty information statement and to change the labor operation. Please discard Corporate Bulletin Number 09-06-04-011 (Section 06 - Engine Controls)
Condition
Some customers may comment that the MIL is illuminated.
Technicians may find DTCs P0420 and/or P0430 set as current or in history.
Cause
This condition may be caused by the ECM determining that either/both of the catalytic converters are exhibiting low efficiency under certain vehicle operating conditions.
Correction
Important
DO NOT replace the catalytic converters for this condition.
A revised calibration has been released to address this condition. Follow the published SI diagnostics for DTC P0420 or P0430 and repair if necessary. If the SI diagnostics do not isolate a cause for this condition, reprogram the ECM using the Service Programming System (SPS) with the latest calibration available on TIS2WEB. Refer to the SPS procedures in SI.
When using a multiple diagnostic interface (MDI) for reprogramming, ensure that it is updated with the latest software version.
When using a Tech 2(R) for reprogramming, ensure that it is updated with the latest software version.
During programming, the battery voltage must be maintained within the proper range of 12-15 volts. Only use the approved Midtronics(R) PSC 550 Battery Maintainer (SPS Programming Support Tool EL-49642) or equivalent during programming.
TECHNICAL
Bulletin No.: 09-06-04-011A
Date: April 03, 2009
Subject:
Malfunction Indicator Lamp (MIL) Illuminated, DTCs P0420 and/or P0430 Set (Reprogram Engine Control Module (ECM))
Models:
2007-2008 Chevrolet Corvette ZO6
2009 Chevrolet Corvette ZO6 Built Prior to VIN Breakpoint 95112736
with 7.0L Engine - RPO LS7
Please Refer to GMVIS
Supercede:
This bulletin is being revised to update the reprogramming emission controller warranty information statement and to change the labor operation. Please discard Corporate Bulletin Number 09-06-04-011 (Section 06 - Engine Controls)
Condition
Some customers may comment that the MIL is illuminated.
Technicians may find DTCs P0420 and/or P0430 set as current or in history.
Cause
This condition may be caused by the ECM determining that either/both of the catalytic converters are exhibiting low efficiency under certain vehicle operating conditions.
Correction
Important
DO NOT replace the catalytic converters for this condition.
A revised calibration has been released to address this condition. Follow the published SI diagnostics for DTC P0420 or P0430 and repair if necessary. If the SI diagnostics do not isolate a cause for this condition, reprogram the ECM using the Service Programming System (SPS) with the latest calibration available on TIS2WEB. Refer to the SPS procedures in SI.
When using a multiple diagnostic interface (MDI) for reprogramming, ensure that it is updated with the latest software version.
When using a Tech 2(R) for reprogramming, ensure that it is updated with the latest software version.
During programming, the battery voltage must be maintained within the proper range of 12-15 volts. Only use the approved Midtronics(R) PSC 550 Battery Maintainer (SPS Programming Support Tool EL-49642) or equivalent during programming.
