p0014 code 2012 Buick Regal 2.4 ecotec

What is your question?

Replaced actuators, oil, filter, crank sensor; has no signs of running poorly, gets 26 -27 mpg, easy start, no sounds from timing chain area; (or other places), light is off sometimes when starting in the morning, comes on at 30 to 60 miles later or 3 miles. still with p0014 code. ECU or wiring or fuel injectors ? how to check ECU for intermittent problems?

What makes this problem better or worse?

no proformance problem

How long has your 2012 Buick Regal had this problem?

few weeks