[jimmypop13]

You'll get codes for the missing cats and those will turn into permanent codes that can not be tuned out without fixing the problem (you can tune out the CEL light but the code stays and screws your emissions test). I had to buy some o2 spacers and put the Big Daddy mini cat o2 sims on those to convince the car the cats were back on and it removed the codes after a few cold starts. Then I could tune them out. If you don't want to tune the car, just get two Big Daddy mini cat o2 sims and see if your codes go away. If not you may have to put o2 spacers in front of them like I did. I never did try the big Daddy mini cat o2 sims by themselves. I already had the o2 spacers so I just used them both together
http://www.bigdaddiesgarage.com/mini-cat-cel-fix.html