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2003 GMC Envoy XL SLE 4.2L Poor Idle Quality, Misfire, MIL Lamp on
Posted to GM Driveability on 12/18/2009 25 Replies

This truck came in with the check engine light on with a p0306. At first customer said he wanted a tune up but realized that the misfire should be checked first. I swapped coils and plugs and miss remained on #6. Put a vacuum gauge on it and had a nice steady ...

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  Related Documents & Media  2003 GMC Envoy XL SLE

 
Message Closed w/FIX

car Vehicle Data

2003 GMC Envoy XL SLE

VIN 1GKES16S63
Engine4.2 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI
EmissionsOBD-II Compliant
SymptomsPoor Idle Quality, Misfire, MIL Lamp On
OccursAlways

Trouble Codes

P0306Cylinder 6 Misfire Detected
Message Closed w/FIX

car Vehicle Data

2003 GMC Envoy XL SLE

VIN 1GKES16S63
Engine4.2 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI
EmissionsOBD-II Compliant
SymptomsPoor Idle Quality, Misfire, MIL Lamp On
OccursAlways

Trouble Codes

P0306Cylinder 6 Misfire Detected