First of all, I apologize if this is in the wrong forum. I'm new here and this is my first post. Also, I am still a huge noob on cars and learning bit by bit.

So I recently got a muffler delete done to discover that my cute little 4-banger is loud. Crazy loud. Enough to rattle windows. It seemed to be a little abnormal. Turns out the previous owner hollowed out the converter and rigged the O2 sensor to not trip the service light. I discovered this after replacing the sensor after I had the stock muffler put back on.

So now the service light is on for the converter and I understand why the thing is so damn loud with no muffler. In a week I'm having a magnaflow muffler put on instead but I'm still debating whether to fix the cat or not.
So my question is this: Can I get a tune to run without the cat or at the very least, get it to quit tripping the service light without rigging the O2 sensor again.

 

you can tune it out ... but if rasp and loudness are anoying to you, mostly everyone hates rasp (dont wana be mistaken for a civic lmao)

if you want a good CAT, i would just buy a catted dp and get the muffler fixed and you should sound normal

 

what model is your cobalt by the way? 2.2? 2.4? supercharged? turbo?

welcome to the boards

 

2.0 ss/sc

Also I did the muffler delete in the first place because I wanted a little more noise and a little less back pressure. But I didn't expect the loudness that I got.

 

This^^

ON an Supercharged (LSJ) the exhaust will be LOUD with an aftermarket muffler with the crappy resonator on it.

I grabbed the ZZP resonator and it got rid of the drone and Rasp. Sounded good after.

I have a video on youtube somewhere


Oh here it is....

 

Yea its very easy to get raspy on an lsj. OP get a zzp 3 inch downpipe (catless will be more throaty but catted is for emmissions) and an aftermarket resonator and throw on ur magnaflow and urs will sound
close to his. You can get an extended o2 bung and clear the code and ur cel should stay off. I didnt tho cause it doesnt bother me

 

I have a Rugged Ridge cat back exhaust and I definately have cats. The JK cats are up front. You're not wrong. If you basically installed an exhaust from the rear axle back you definately have cats. It would be a process to remove the cats, you would know it. You don't have the original muffler or a resonator. Again, someone at a dealer who doesn't know what they're talking about.