Avg mpg reset

[Derrickpzo]

What's up all . Have an 05 Sierra slt z71 5.3L runs , looks and sounds fantastic except lifter tick at start but I'm ok for now. After this virus passes I'll dig into that . Now I just reset my avg econ while it was raining out just setting the scene and took a short ride I have a super annoying buzz rattle coming from dash cluster . Is there a counter on 05 that runs for a certain amount of time , or is it just a coincidence it happened at exactly the same time. Any thoughts would be appreciated thanks. Stay safe all it's nuts out there.

[terry2004]

when the noise in the dash starts ,move the airvent selector to a new setting .floor back to defrost .see if that makes a difference .The air door can get stuck.