I’m not going to lie here: my mechanical knowledge is almost nonexistent.

My car is in the shop getting a Dynomax Ultra Flo cat back exhaust system installed. I asked them to delete the cat and use a Y pipe because I figured my cat wasv going to die eventually anyway.

Assuming the shop does everything correctly, am I at risk of throwing codes? There is still time to tell them to leave the cat on if the delete/Y pipe mod is a bad idea.

Thank you!

 

I'm surprised the shop will even do it. EPA is getting more aggressive about fining shops for stuff like that. And they're nasty big fines.

 

If you think that's the dumbest question ever asked on this site, you must be new here.

Unless the O2 sensor is damaged during the cat removal, you shouldn't see any DTCs.

 

I was surprised they suggested it too, but in TX there are no emissions requirements for cars over 25 years old, so maybe that’s how they can get away with it. The shop is a really high quality, reputable business. I’ve been going there for years.

Also, even if they go to replace the cat, the O2 sensor could potentially be damaged, so it’s kind of damned if you do, damned if you don’t, right?

 

Unless your shop is using high explosives or a giant mech to remove your cat your o2 should be fine and well away from where they’re working.

But on to what emissions laws are in Tx, even if your vehicle is no longer emissions tested all factory emissions equipment must still be present. I don’t know where in Tx you live but as long as you’re not in the big metropolitan areas and don’t go to a nationwide chain to get your safety inspection you likely won’t have an issue. Unfortunately that’s all I have. I’m new to DFW and don’t have a new shop I know of yet for inspections that doesn’t care what’s under the car.

 

 

very true. I remember one dude made a post asking what tires would squeal the loudest because he liked doing burnouts and having tires that made loud screeching sounds. He beat OP by a mile.