Crappy Scenario, advice needed please.

About a week ago I woke up to drive to work... It wouldnt start. So I dealt with it after I found a ride and came back home. I Excluded out everything including the bat, alt. Then I started to think to myself and I realized the ignition was super, super loose. I took my steering column apart and I found the bolt that held the ignition in place. I put a new bolt in there and it started.... yay, but heres the ****... I went to work that next day and the engine began to bog, and It died at a stop light, Then the cel came on then went off 5 minutes later. Anyways I took it to a mechanic had him through in a axel which I needed, and they havnt figured anything out yet as with why it dies.

Could this be that I may have filled my car with regular gas??


Anyways, It only dies when Im not moving.

I had them check the cel codes and they think it was my oxygen, could this cause it??

[ssnsltd]

Not the gas. I have run both mine on regular and mid-grade just to make a comparison