gas cap (chec engine light) on 2004 Cadillac Escalade EXT

problem with ACDELCO PART # GT264 LOCKING GAS CAP for 2004 cadillac truck

Asked by for the 2004 Cadillac Escalade EXT
I'd get a computer diagnostic. A failed EVAP solenoid is a common thing on these and will turn the "check gas cap" message on.
If the gas cap's seal ring is good and the cap is tight there is a possible EVAP solenoid failure or a leak somewhere else on the EVAP system.