engine is on

after most repairs you need to reset the check engine light, and in the cas of evaporative emissions it will not know you have corrected the concern until it reruns it's self diagnostic, for a gas cap code, it could take a while, i would have someone reset the light, and make sure it was only a gas cap and not a small leak in the evap system.

ok ty will try that but i have a hand held check put cap on but after i took code off it came back later