2006 Chevy Silverado tighten fuel cap warning

2006 CHEVROLET SILVERADO
28,000 MILES • V8 • 4WD • AUTOMATIC
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BOLTONR
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  • 1 POST
I got a tighten fuel cap warning and then the check engine light came on. Tightening the fuel cap did not fix the problem, so I bought an OEM replacement which immediately fixed the problem for about one month and 500 miles of driving. Now I have the same problem.
May 7, 2010 at 7:40 AM
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BLUELIGHTNIN6
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  • 16,542 POSTS
There are all sorts of things that can cause that issue. The evaporative emissions system runs a test to ensure no fuel vapors are escaping into the atmosphere. The vehicle simply assumes the gas cap is loose based on the rate of leakage. It could be a leak at the filler neck, tank itself and/or any of the evap valves. This doesnt mean it leaks fuel, but rather fuel vapors from the emissions system.
May 7, 2010 at 11:30 AM