Very often vacuum leak does not go to that extent...but hidden somewhere...and need to find...most cases are minor so far. A few customers we couldnt find..and reluctant to pursue because how do you charge?...if need 10 days to find...and just repair a hole...how much? $50? $100? .it does not make economical sense at all.Vacuum leak can be bad. Will cause engine to run rich and clog up the Cat...