[Lilmink]

Started off with 3 codes, P1126, P1130 and P1133. Cleared the codes and drove a bit and the 1130 did not come back. Added a full tank of high octane gasoline and a bottle of fuel system cleaner. Cleared codes, drove a bit. CEL came back with only the P1126 (Oxygen Sensing Adaptation, Lower Load Range, Bank 1) Took apart the MAF and cleaned it. Not experiencing any loss of power, acceleration, car runs smooth as could be when Idle. There is a very slight change in how it runs if it is started cold but that goes away after a few seconds.

Tried the oil cap test not sure what these results mean but when I take the cap off engine gets very loud and rough. Back to normal with cap on.

Long term fuel trims are stuck at 31.3 this doesn't change with at Idle or 2500rpm not sure if it will take the computer some time to catch up with this.

Is smoke test my next step of diagnosis? How can I test the O2 sensors before replacing them? I see on my scanner it provides the voltage the o2 sensors are running at.