I really hope someone can give me some idea of what is going on with my car. It is a 99 z28 m6.

Here is the story, the car hesitates under throttle pretty noticably, My dad had a MAF from a Z06 which we thought would fit just to try a new part. We put it in and plugged it in, the car ran great, however later we realized that it was the wrong part and all we really accomplished was running the car with no MAF. It immediatly threw a SES light. I thought a bad MAF would make the car run goofy . so I ordered a new SLP (The right one) I hooked it up today, reset the computer and the problem is still there, although maybe a tad less noticable. I have no clue what could be wrong. The plugs are fine, some people have mentioned o2 sensors however i dont have $300 to "test" if that is what the problem is. The car isnt throwing any codes so I am really walking in the dark.

 

did the car run fine before the first maf?