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The engine light is not specific to any one thing. It is only meant to inform the driver that there is a problem with engine management / emissions control.
This light comes on when the car's engine management system senses an emissions impacting fault. This has nothing to do with oil service, coolant level, or any regular maintenance items. This light is caused a failed component or operating range out of spec. There is a problem with the engine / engine management / emission control systems or one of the inputs that it uses to operate properly / efficiently.
There are dozens and dozens and dozens of reasons (actually close to 200 reasons) for this light to come on. The good news is that when this light is triggered, the car logs a descriptive fault in its computer which can then be read out to shed some additional light on the problem.
The only way to determine why this light is on is to have the fault memory read from the car using a compatible scan tool. Once the fault memory is read, the failed component or issue can be identified and replaced/repaired, and the light switched off. Some parts stores will read the faults for free, so check with those near you. If you cannot find a local parts store that scans faults for free, then you will need to pay to have the memory read out at a shop with the proper equipment (the place that did the oil change should have at least a basic code reader). There is no alternative to having the fault logs read out – there is no way to guess the problem, and attempting to do so would get very expensive, very quickly.
If the car still seems to be operating normally, it is most likely just an emissions related sensor that has failed, or something to do with the evaporative emissions control system or possibly a loose gas cap, but again, the fault memory MUST be read in order to verify the cause. And again, the light will not go off until the underlying issue is fixed.
it is unlikely that anything would be touched during the course of an oil change that would cause the light.
Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you. Best wishes with your vehicle.