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2001 Pontiac Bonneville SLE 3.8L MIL Lamp on
Posted to GM Driveability on 2/3/2010 9 Replies

Hello all, This Bonneville sets a P0420 converter code randomly. It typically happens at idle. It first came to me with an aftermarket converter that was very small. I connected my scanner and monitored fuel trims and watched the Upstream and downstream o2's. ...

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  Related Documents & Media  2001 Pontiac Bonneville SLE

 
Message Closed w/FIX

car Vehicle Data

2001 Pontiac Bonneville SLE

VIN 1G2HY54K81
Engine3.8 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

2001 Pontiac Bonneville SLE

VIN 1G2HY54K81
Engine3.8 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI
EmissionsOBD-II Compliant
SymptomsMIL Lamp On
OccursIdle

Trouble Codes

P0420Catalyst Efficiency Below Threshold (Bank 1)