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2002 GMC Envoy SLE 4.2L MIL Lamp on
Posted to GM Driveability on 4/27/2009 9 Replies

Hi guys,

This Envoy came in several weeks ago with a p0420a cat efficiancy code and after watching the rear O2 sensor trace on my genisys i saw it would periodically flat line. The code came back after a couple of weeks and seeing a normal but high voltage g...

9 Replies Received (View Replies)

  Related Documents & Media  2002 GMC Envoy SLE

 
Message Closed w/FIX

car Vehicle Data

2002 GMC Envoy SLE

VIN 1GKDS13572
Engine4.2 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI
EmissionsOBD-II Compliant
SymptomsMIL Lamp On
OccursIdle

Trouble Codes

P0420Catalyst Efficiency Below Threshold (Bank 1)
Message Closed w/FIX

car Vehicle Data

2002 GMC Envoy SLE

VIN 1GKDS13572
Engine4.2 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI
EmissionsOBD-II Compliant
SymptomsMIL Lamp On
OccursIdle

Trouble Codes

P0420Catalyst Efficiency Below Threshold (Bank 1)