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1999 GMC C7500 7.4L Excessive Emissions, Misfire
Posted to GM Driveability on 6/9/2008 3 Replies

Although this truck has OBD II communications protocol, it isn't truely OBD II. For instance, it doesn't have a downstream O2S & there's no Mode 6 data. There are no DTCs. Many of the Tech II functions work fine, but there are no misfire functions. The Cylinde...

3 Replies Received (View Replies)

 
Message Closed w/FIX

car Vehicle Data

1999 GMC C7500

VIN 1GDL7H1D1X
Engine7.4 L / 8 cyl
DeliveryFI / SEFI
EmissionsOBD-II Compliant
SymptomsExcessive Emissions, Misfire
OccursAlways
Message Closed w/FIX

car Vehicle Data

1999 GMC C7500

VIN 1GDL7H1D1X
Engine7.4 L / 8 cyl
DeliveryFI / SEFI
EmissionsOBD-II Compliant
SymptomsExcessive Emissions, Misfire
OccursAlways