Great. Check Engine light is on and engine is shaking furiously in its brackets. I don't think it wants to be checked...
The check engine light just malfunctioned and now the engine got told "Hey, the check engine light is on, something might be wrong with you!" Which means your engine is scared now and is being hypochondriac about anything and everything.
Just read wikipedia pages of different types of cancer or illnesses and you know how it feels right now.
Disclaimer: Research on self-awareness of combustion engines is spare and theories used in this advice are still under debate in the scientific community. To fund further research please donate to the Society for the Combustion engine Awareness Movement (SCAM). Thank you very much!