check engine light on, failed emissions test, could it be a vacuum leak? or???? on 2004 Buick Rendezvous

2004 buick rendezvous. it's not the gas cap, or pers sensor. would a vacuum leak make it fail emission test? what would a ballpark figure be for cost to fix. Could it be part of the recall??

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1 answer 1 comment
several things will cause a failure. seek a diag from a good mech that has a smoke mach and good scan tools
Thanks, I'm going to Autozone this morning to do the check and then to the mechanic. Thanks for your reply.