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2003 Chevrolet Impala LS 3.8L MIL Lamp on
Posted to GM Driveability on 9/17/2012 16 Replies

repeat P0420 [...] conv 3x. no coolant loss,uses 1 qt oil per service, replaced o2 both,conv temp 550 frt/650+ rear, hot rear O2 [...] fairly flatline. calc load max of 87%. when code stores(freeze frame)closed loop,LTFT has been 126 and 129 not right rpm 657,...

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  Related Documents & Media  2003 Chevrolet Impala LS

 
Message Closed w/Summary

car Vehicle Data

2003 Chevrolet Impala LS

VIN 2G1WH52K13
Engine3.8 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFuel Injection
EmissionsOBD-II Compliant
SymptomsMIL Lamp On
OccursIntermittently

Trouble Codes

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

car Vehicle Data

2003 Chevrolet Impala LS

VIN 2G1WH52K13
Engine3.8 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFuel Injection
EmissionsOBD-II Compliant
SymptomsMIL Lamp On
OccursIntermittently

Trouble Codes

P0420Catalyst Efficiency Below Threshold (Bank 1)