Possibly need some help
 

Hi...

I got a problem (i think)...
i had a full turbo back on my car, with catless dp.. and upipe
and a hks ssqv.

welp, a while ago a got pulled over and i had to go back to stock, but when
i went back to stock piping, my car still sounded a little louder then stock.

i have the check engine Light, ever since i put on the turboback, and when
i changed back to stock the light still stayed...

Also, I think i should note that I tried to put on the stock bov... but the car
would go into idle mode (possible leak in stock bov?), so i put my hks back on
and it worked fine...

Oh yeah, I still also havent changed out the stock air filter yet @ 30k miles, if that matters any.

I guess my question is, does anybody think it should be something i should be worried about, (that my car sounds a bit louder then stock) ?
what could the potential problems be if any? (my car runs fine right now)

Thanks in Advance :)