Cat deletes
#22
GT Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: April 23, 2013
Location: New York
Posts: 152
Likes: 0
Received 0 Likes
on
0 Posts
The garage door is always opened, I sadly know people who worked on cars (guy owned his own shop) and sadly passed away from poor ventilation, so I open the garage door as soon as I step into the garage.
But I guess cats are coming out in the spring.
#24
GT Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: April 23, 2013
Location: New York
Posts: 152
Likes: 0
Received 0 Likes
on
0 Posts
#25
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Yes, it's illegal....yes, it's irresponsble (if you care about such things...which many obviously don't) and yes, the smell is completely obvious the the police officer or anyone who is riding behind you in traffic.
You can pick up a few horsies but cost:benefit doesn't seem favorable on this mod.
You can pick up a few horsies but cost:benefit doesn't seem favorable on this mod.
#26
Last edited by Ballard423; 12/3/19 at 09:06 AM.
#27
Legacy TMS Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: January 25, 2010
Location: Massachusetts
Posts: 3,811
Received 1,538 Likes
on
1,053 Posts
I have the axle back slp exhaust. But when you say throw the code if I dont go have those things turned off will the check engine light stay on or will it make the car run sluggish like with a bog? Cause if I go hop in my car on a cold day without letting it warm up first my check engine light will flash and the car will bog run sluggish till I pull over and let the engine warm a bit. 2014 5.0
The rear O2 sensors are downstream of the cats and my understanding is that their sole purpose is to see whether the cats are working or not; they are used for emissions inspections but have no impact at all on the way the car runs. If you have physically removed the rear O2's but have not turned them off in the tune, then the computer will complain by turning on the check engine light.
Your issue is probably caused by something else; possibly the front O2's which are used to fine-tune the air/fuel mix.
#28
"Axle back" is fancy new wording for "mufflers" and normally that does not affect the Catalytic Converters so i am not sure what you are getting at. Have you removed the cats?
The rear O2 sensors are downstream of the cats and my understanding is that their sole purpose is to see whether the cats are working or not; they are used for emissions inspections but have no impact at all on the way the car runs. If you have physically removed the rear O2's but have not turned them off in the tune, then the computer will complain by turning on the check engine light.
Your issue is probably caused by something else; possibly the front O2's which are used to fine-tune the air/fuel mix.
The rear O2 sensors are downstream of the cats and my understanding is that their sole purpose is to see whether the cats are working or not; they are used for emissions inspections but have no impact at all on the way the car runs. If you have physically removed the rear O2's but have not turned them off in the tune, then the computer will complain by turning on the check engine light.
Your issue is probably caused by something else; possibly the front O2's which are used to fine-tune the air/fuel mix.
#30
Legacy TMS Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: January 25, 2010
Location: Massachusetts
Posts: 3,811
Received 1,538 Likes
on
1,053 Posts
I want to delete the upper cats that run to the H pipe but plug the upper 02 sensors back in. From what I'm understanding is that it's going to throw the check engine light. What I was wondering is when it triggers the check engine light is that going to effect the car's performance in any way
The rear/downstream O2 sensors will trigger the Check Engine light, but it does not affect the operation or performance of the engine.
I assume you already read all the reasons not to delete the cats earlier in this thread so I won't say it all again.
Last edited by Bert; 12/4/19 at 04:55 AM.
#31
Banned
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: August 2, 2013
Location: Little north of Stuttgart, Germany
Posts: 3,090
Received 254 Likes
on
230 Posts
why not go with a high flow CAT? Catalytic converters are the reason you can breathe normally in any major US city. I started appreciating them after a trip to India. Fog like smog burning your eyes and lungs.
Anyway, catted pipes still give you good sound increase and performance gain. They cost more though.
Anyway, catted pipes still give you good sound increase and performance gain. They cost more though.
#32
Legacy TMS Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
why not go with a high flow CAT? Catalytic converters are the reason you can breathe normally in any major US city. I started appreciating them after a trip to India. Fog like smog burning your eyes and lungs.
Anyway, catted pipes still give you good sound increase and performance gain. They cost more though.
Anyway, catted pipes still give you good sound increase and performance gain. They cost more though.
Thread
Thread Starter
Forum
Replies
Last Post