Rough Coast and Random Misfire
 

Hey all,

Just started having a particular issue with my 2003 Silverado the other day:

The truck runs fine for the most part, but whenever I let off the brakes to coast for a second, such as when I'm in traffic and only need to move a few feet, the truck starts knocking pretty bad. It doesn't idle rough when in park, or when I'm completely stopped.

I know there are a wide range of possible issues with generic rough idle, but I couldn't find any topics on the internet pertaining to this kind of situation.

I checked around for any of the basic vacuum leaks but I'm still learning more of the intermediate / advanced troubleshooting skills. Any help would be appreciated!

--Mike