Let me rephrase then. Let's assume the check engine light is on due to a fault in the fuel pump. You can clear the code but you aren't clearing the problem. As soon as the problem occurs again, the light returns. In most cases the faults that trigger 'check engine' lights are in a constant state of fault until the part is repaired or replaced meaning the light will return essentially as soon as you press the accelerator.
One of the most common causes for the "check engine" light to come on is a loose gas cap. That's something I'm happy to be able to address and clear all on my own.
Granted, I tighten my gas caps like a gorilla these days.
