Hello all, I know this isn't a camaro but you've got the best chevy site around. I have a 229 v-6 in this old bird and flunked the emissions for nitrous oxides. I assume that my cylinders are running too hot. My egr valve is fine but I think my passages may be clogged as its common with this engine. Any good ways to clean them out I tried a wire hanger but didn't work very well, I was considering avaition cable in my drill and boring through the carbon. Anyone have any better options?