GMC Truck Forum banner
1 - 20 of 40 Posts

·
Registered
Joined
·
3,394 Posts
Discussion Starter · #1 ·
Well good news, about to move my registration to Mariposa county in cali. That means no smog for me. Anyways, I want to remove my cats and keep everything the same for now. Ill deal with the longtubes and true duals later haha but anyways I was curious about the 3rd 02 sensor that is behind the cat? How do I disable that one? Tried searching but no luck. Thanks. :worship:
 

·
AllOffTopic.com FTW!
Joined
·
8,460 Posts
You'll need a tune to ignore the sensor, or an O2 sensor simulator.

Besides smog inspections, there are federal laws prohibiting the removal of cats and other emissions devices. I don't know how they're enforced and have never heard of them being enforced.
 

·
Registered
Joined
·
3,394 Posts
Discussion Starter · #4 ·
Around here its kind of like a fix-it ticket. Just like tinted windows, just considered too loud of exhaust if I am not mistaken. Would a tune from say Black Bear do the trick?
 

·
Registered
Joined
·
3,394 Posts
Discussion Starter · #5 ·
Umm, 3rd 02? Rofljest.
Bank 1 or 2?


You won't see any gains on stock manifolds anyway.
Kind of lost me here man. Its more for the sound, I read that removal of the cats dont really help anyways. Might just put it off though and do it all right, you know headers, cutouts, x pipes, true duals...
 

·
I don't have a truck
Joined
·
10,439 Posts
Around here its kind of like a fix-it ticket. Just like tinted windows, just considered too loud of exhaust if I am not mistaken. Would a tune from say Black Bear do the trick?
No, that's wrong. FEDERAL guidelines, 50 state wide, prohibit it. It's not a fix it ticket, it's a huge fine per cat. You might receive a loud exhaust ticket as a result, but you can be fined up to $1000 per cat IIRC.
 

·
I don't have a truck
Joined
·
10,439 Posts
Kind of lost me here man. Its more for the sound, I read that removal of the cats dont really help anyways. Might just put it off though and do it all right, you know headers, cutouts, x pipes, true duals...
You have 2 precat and 2 postcat o2's. One on one side and one on the other, (bank 1 and 2). The precat sensors monitor air fuel ratio and the post cat sensors do nothing but make sure the cat Is in place and working correctly.
There Is not a 3rd 02 per bank, there Is 2 per bank and you'll need to have the rear 02's tuned out if you don't want a check engine light. Honestly it's not even worth all that with stock manifolds.
 

·
I don't have a truck
Joined
·
10,439 Posts
I know I can't talk you out of it but you'll still have to get your truck inspected and you'll still have a visual inspection. The tech knows what cats sound like and when cats are removed. I would be nervous as shit taking a catless truck for inspection in a place like commie-fornia. Its a huge fine plus you'll have to buy new cats and possibly have your truck impounded.


Get some carb legal mids and be done with it.
 

·
Registered
Joined
·
3,394 Posts
Discussion Starter · #10 ·
decided not to do it. but i could only see one other o2 sensor so i guess theres the confusion. when i said fix it ticket i meant for loud exhaust. my buddy is runnin no cats in his 383 and they never checked it out. and last i dont have to do inspections or smog. theres a few counties in cali that you only smog when you sell
 

·
Banned
Joined
·
1,500 Posts
mine are getting gutted with pipe welded into the case as soon as i get my tune sometime next week hopefully. but, both of my o2 sensors are throwing codes and my catalytic converters are bad and $200 is cheaper than those 4 parts. if youre gonna do something like that atleast make buddies with a shop that passes people they like.
 

·
GMFS Military Member
Joined
·
10,899 Posts
mine are getting gutted with pipe welded into the case as soon as i get my tune sometime next week hopefully. but, both of my o2 sensors are throwing codes and my catalytic converters are bad and $200 is cheaper than those 4 parts. if youre gonna do something like that atleast make buddies with a shop that passes people they like.
Oklahoma has emissions? :wtf:
 

·
Registered
Joined
·
3,394 Posts
Discussion Starter · #13 ·
Ya we will see in case. My uncle owns two dealerships and my other uncle runs the service department so I need to have a talk with him about that in case I do end up having to smog.
 

·
Registered
Joined
·
564 Posts
kids in my hometown have been depleting the atmosphere for years, dual exhaust with straits or glasspacks, all you need is a tune to take care of the computer...
 

·
Banned
Joined
·
1,500 Posts
Oklahoma has emissions? :wtf:
nope, no inspection no emissions no nothin. im just keeping those on there for if/when they do bring it back. and so when i get pulled over if a cop decides to look under i wont get a fine or anything.
 

·
┌∩┐(º_º)┌∩┐
Joined
·
363 Posts
When i did my longtubes i left the sensors plugged in and just ziptied them to the frame. Check engine light is on, but other than that, i don't notice a difference, other than the performance gain from the longtubes. I'll deal with the CEL till i get around to getting a tune. And i dont live in an area with any sort of testing, visual or otherwise, so big fucking deal.

And LMAO at saying you lose low end torque. That's comical. 5.3, 1.75" primaries, 3" collectors and exhaust and i had no loss of torque anywhere.
 
1 - 20 of 40 Posts
Top