My check engine light comes on frequently and when i push the onstar button for them to run a diagnostic check they say it is an emissions problem and to take it in if the light does not turn off 7 more times after running your vehicle. This becomes annoying when you take it to the dealer and they want to charge you for checking out the vehicle and just say they needed to replace the gas cap, and then the light is reset, then a month or two later the light turns on again and it is the same issue, instead of just replacing the cap fix the real problem and stop charging people to make money!
tighten fuel cap notification comes on - and then goes off.
haven't replaced cap yet
now have check engine light...
Engine light on saying loose fuel cap ,replaced problem continues to this day
Since I've bought my denali the engine light came on after my second time getting gas to present.
same problem changing the cap tomorrow
Same issue with my yukon, light is on and I replaced gas cap. Check engine light is still on
Had the same proble shortly after purchasing my vehicle. Dealer replaced gas cap and no further problems.