May faulty gas cap, need replace it. Compatible With Vehicles: The fuel cap is compatible with Chevy, Cadillac and GMC vehicles, compatible with Silverado 1500 2007-2011, Tahoe 2007-2011, Avalanche 2007-2011, Escalade(ESV EXT) 2009-2011, Sierra 1500 2007-2011, Yukon Yukon XL 2007 2011.
