Check engine light comes on when oil tank overfilled

SOURCE: engine light after i overfill gaz tank 2004 4runner

The light didnt come one because you filled it =while it was running, its on because you overfilled it. You pushed gasoline passed the rollover valve, into the charcoal canister which is probably now saturated. It may push raw fuel into the intake, which will make the engine run rough. Chances are, you need a new charcoal canister, ORVR, corrugated hose, and Purge valve

SOURCE: oil level light/smoke from radiator overfill/sludge in same

If oil is Clean and there is no White Smoke that Disapates Fast, Check for Transmission Cooler (IN RADIATER) Problem

SOURCE: My 1991 sedan deville's coolant

sounds like your thermostat

SOURCE: 2000 blazer runs rough after gas tank was overfilled

there is a vapour purge line from the tank to a charcoal cannister. The line& cannister has been contaminated with liquid gas. When the engine attempts a normal purge from cannister it gets loaded with raw gas, causing rough running and cherck engine light. Replace cannister. Never over fill gas tank, especially on hot sunny days

SOURCE: Engine light comes on. Checked gas cap and filled

Over 200 things can cause "check engine" light. Some Les something tire stores will diagnose code for free. Good luck Techjoel