somrtimes this light goes on after each 1/4 tank of gas gets used. I have a saturn ion, and for the whole winter this happened. Now spring and it went away. Just a few days back it went on when my tank was 3/4 full. Has not come on since,the tank has been refilled. the engine light stay solid no blinking.
That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.
Regarding warning lights:
if the coolant temp light comes on, shut off the engine ASAP
if the oil warning light comes on, shut off the engine ASAP
if a FLASHING MIL/CEL comes on, shut off the engine ASAP
ASAP means driving to the berm of the highway right now and not waiting for the next exit.
But if the MIL/CEL is not flashing, then it’s not an urgent indicator.
Eventually you will need to get it scanned. Some here say Autozone will give you the numbers, don’t just get the name. The mechanics here like the raw numbers.
This is the sort of thing that makes one suspect the gas tank seal. If there is a leak, or the cap is bad or not properly tightened, there will be a failure.
Some of these can be hairy, I tell you. In my case, an intermittent ended up being the canister assembly, probably a sticky low pressure valve.
Get the numbers.