Strange behavior but no code, should I worry?

[wawa]

Well no CEL but there is 2 pending code on my code reader.

P0507 - Idle Air Control - Idle Speed Too High (that match the idle going up to 2k than jump down at 1k)

P1126 - Oxygen Sensing Adaptation Area 1 (Cylinders 4 - 6) - Rich Threshold

What could cause that with all other symptoms?

Later
wawa

[wawa]

Well I losen the belt and all elements seam to turn freely without noise. I also start again the engin and no noise so I dont think the noise was releated to my problem. But when i started the car it did a good smoke clould kinda blue. I'm really starting to think about a fuel problem.

later
wawa