
2001 Chevrolet Impala LS 3.8L P0420
Have run car on Modis and shows OK. Fuel at speed looks good. Map and maf in range. LT fuel trim show -6 to -2 as you drive down the road log flat strech shows +2 to -3. Temp OK timing and all els look in spec. What have I missed?
FIX posted 3/22/2005
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Message Closed
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VIN | 2G1WH55K81 |
Engine | 3.8 L / 6 cyl / GAS |
Trans | 4-speed Automatic (Electronic) |
Delivery | FI / EFI |
Emissions | OBD-II Compliant |
Symptoms | P0420 |
Occurs | Intermittently |
Trouble Codes
P0420 | Catalyst Efficiency Below Threshold (Bank 1) |
Message Closed
Vehicle Data
2001 Chevrolet Impala LS
VIN | 2G1WH55K81 |
Engine | 3.8 L / 6 cyl / GAS |
Trans | 4-speed Automatic (Electronic) |
Delivery | FI / EFI |
Emissions | OBD-II Compliant |
Symptoms | P0420 |
Occurs | Intermittently |
Trouble Codes
P0420 | Catalyst Efficiency Below Threshold (Bank 1) |