Also, even if there were not all problems generate a code, and not all codes trigger the CEL. The fuel delivery system is only partially controlled by the computer and the FP regulator is not under computer control so a proplem there would not in itself generate a code. If the problem in turn affected other systems then a code might be generated, such as A/F ratio and its' affect on the O2 sensors...

You could still pull the codes and check them, there may indeed be codes stored in the computer.