Fuel

[jddeel]

Where is the fuel test port located on the 6600 Duramax Diesel

[Duramaster]

Let's start with What year truck is it? Unless you are dealing with a new C-4500 or 5500 then the fuel test port is near the alternator. There should be a black plastic cap over the fitting. Why do you ask? :confused:

[jddeel]

Thanks, Most all my work has been on gas engine drivability not diesel. Now there are more diesel trucks in our area with chevy and GMC sales increasing.