Check engine light 3700 miles

[GMh8tr72]

I was blessed with the check engine light on a 2 month old Trail Boss.  So disappointed with GM at this point.  My 2014 GMC was a money pit and this is off to bad start.  Yes, it is under warranty but 3700 miles is terrible.  No idea what it is yet, but dealer wants me to schedule appointment and drop off.  Why?? New truck and going down same path as previous.  I post this out of frustration to GM considering I thought I could leave the previous money pit . Yes, this will be warranty but it is a sign of more to come.  I hope other are having better experiences with GM

[94yj]

i would run it by oreilly auto parts and have them pull the code the light may be on because of a loose fuel cap  just an idea