My 15 year old suburban pops a CEL about every hundred miles or less for Evap emissions etc. I looked it up and there is some kind of sensor or valve on top of the fuel tank.. i never planned on fixing it, so i keep a small scan tool in the glovebox and just remove the CEL so it doesnt aggravate me.
I have had this vehicle for a couple of years.. it was very lightly maintained so i have been running cleaners here and there (Redline, Techron etc)...always using top tier gas etc. Nothing ever changed that CEL.
I bought the little Gumout Expert Regane that was on clearance at AZ a couple of months ago and have used it two tanks back to back.
The CEL hasnt came on in either of those tanks.. and i usually get at least 2 or 3 CELs per tank..
maybe coincidence but very rarely has anything fixed itself on my vehicles.