Start by having it scanned for any trouble codes. It could be just about anything from a loose gas cap (make sure to tighten it at least three clicks), bad gas cap or seal, to a failing O2 sensor. One strange but seemingly common issue (have heard it more than once from different sources but have not seen it myself) is having a spider build a nest in the EVAP vent hose!
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Wednesday, July 12th, 2017 AT 9:18 PM