True I did not have it hooked to a sniffer after the carb rebuild. I pulled the carb and took it to a very trustworthy carb rebuilder beacuse my accelerator pump was going bad. That is the reason for the rebuild. YES I was a "good boy" and replaced the carb mounting gasket/ plate on the manifold with a new one during the reinstall. I will be sure to check the EGR gasket to see if it has been comprimised. It's just weird that it passed before the rebuild and now it will not. I have not really put that many miles on it between the passing test and the failing tet thats why I am leaning toward air/ fuel mixture. Wouldn't you think that if it had a manifold leak or a vaccume leak the HC would be more than 1000? Keep em coming this is all good info and food for thought.