been there done that as well. that is exactly what happened on mine when they did the fuel injector change. granted, GM doesnt cover the feed lines anymore, but it would have been nice, as Camilleri said, "There is a gm tsb that states that ends of lines need to be glass beaded during injector replacement. this is simply a case of tech not taking enough time to do the job right." mine ended up leaking into the valve covers, and pushing oil out. they replaced one, then it came back, and they did two more, then it came back again, and replaced the rest of them. shoddy work, yes, but i dont think that glass beading would have done anything. the tech who worked on my truck told me about it, and that it didnt work on the last 3 sets he did. but, at this point in my relationship with him, im not sure what to believe. the dealer came out good though, they replaced all 8 at no charge for parts or labor