1. A method comprising: inducting vapors from a fuel system into an engine; conducting a test for undesired vapor emissions from the fuel system after the vapor inducting is stopped; generating a final overall confidence value in a result of the test for undesired vapor emissions based on one or more engine operating conditions, the final overall confidence value being an average of a plurality of confidence levels that indicate an outcome for the test, the plurality of confidence levels being responsive to test entry conditions; generating a weighting factor from the final overall confidence value; applying the weighting factor to the result to indicate undesired emissions; and indicating undesired emissions by an indicator display.