This is the problem I get when I was experimenting with my mass air sensor screens off. The engine light always comes on when I'm at low throttle and rpm while the car is moving.
The issue is related to turbulance within the intake. I would check that your mass air sensor is in the upright position. I recall from a picture that your mass air sensor was sidways, see below. You might want to change it's position. You should also check any loose connetions before the mass air sensor. Also check for any debrit blocking your filter to prevent turbulant air intake.
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