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2002 Chevrolet Monte Carlo SS 3.8L Excessive Emissions, MIL Lamp on
Posted to GM Driveability on 1/25/2008 23 Replies

P0420 MIL keeps returning - low catalatic converter efficiency. catalyic converter was plugged replaced catalyic converter with aftermarket one, also replaced rear o2 sensor with aftermarket one,

Is it a ECM flash problem?, or an aftermarket parts are not per...

23 Replies Received (View Replies)

  Related Documents & Media  2002 Chevrolet Monte Carlo SS

 
Message Closed w/Summary

car Vehicle Data

2002 Chevrolet Monte Carlo SS

VIN 2G1WX15K22
Engine3.8 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI / SEFI
EmissionsOBD-II Compliant
SymptomsExcessive Emissions, MIL Lamp On
Misc.Ss

Trouble Codes

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

car Vehicle Data

2002 Chevrolet Monte Carlo SS

VIN 2G1WX15K22
Engine3.8 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI / SEFI
EmissionsOBD-II Compliant
SymptomsExcessive Emissions, MIL Lamp On
Misc.Ss

Trouble Codes

P0420Catalyst Efficiency Below Threshold (Bank 1)