You get a CEL, but your OBD scanner is locked in your other car, out of town...

UPDATE: And it went out on its own. Only 3 things I did:

- Tighten the gas cap (it was already clicking)

- Shake my intake a bit and wiggle the MAF sensor to see if it’s loose (it wasn’t)

- Stop by the local Chevy dealer to ask how much to do the code scan (one further away said it was free) and this dealer quoted $160 to “diagnose”, so I started my car to leave.

It was right at that moment when I was about to leave the Chevy dealer, light’s gone.