The carburetor was replaced, now there is a vacuum leak.
If a vacuum leak occurred right after the carburetor was replaced then the gasket underneath it was not installed properly, is missing, or the vacuum hoses were not installed correctly. Prior to removing the carburetor I would double check the connection of the hoses and see if any need to be replaced. If the hoses are all fine then see if the carburetor gasket was installed correctly. If that is fine also then it may not have a vacuum leak. The problem may be in the fuel mixture and the carburetor may just require adjustment. This can be a difficult task, even for a mechanic, if they do not have a lot of experience with tuning carburetors.
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