Can I bypass the last cat?


Long Rider

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Can I bypass the last catalytic converter on an 05 Rubicon? The primary cats died on my TJ. I ordered Magnaflow primary cats and manifold, but cannot afford the last or secondary cat. Can I bypass the last cat since the O2 sensors are on either side of the two cats near the engine?

I'm thinking I will run fine as long, but do not know if it will pass emissions. I live in Texas. Does anyone know if they do visuals here in Tejas, or do they just interrogate OBDII?
 

Jodh

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I would guess it depends on where you go. I've never had them look at anything underneath. As long as the check engine light isn't on you're good. What part of Dallas you in maybe I can send you to some good places?
 

scottgraham

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I haven't lived in Texas for about 15 years, but I never had to smog.
I also lived in small towns (haven't lived in Dallas in 30 years thank gawd) which may or may not make a difference. If I recall, down there if a vehicle is over "X" years old, no emissions is required.
BTW: You can just knock all the beads out of that third cat if you are deleting.
 

KingCarGuyZ

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smogged last month in Frisco (suburb of Dallas), no visual just OBD2. actually had to replace my primary's to pass, should've replace my "Main", but it's $$$. you'll be fine so long as it doesn't throw a code (which it shouldn't if you have good primary) there's also a host of other tricks to get your "offroad only vehicle" to not throw a CEL if you need those. 😁

Edit, if you need a guy that doesn't ask too many questions, IK one in the 121 and McDermott area.
 

Tomcat

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Your pre-cats are necessary because there tied into the ECM.
The 3rd cat is not, I deleted my 3rd cat when my pre-cats went to hell and dumped into it. I've had no problems without it, although I dont have inspections here. 06, 4.0
 
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AndyG

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Your pre-cats are necessary because there tied into the ECM.
The 3rd cat is not, I deleted my 3rd cat when my pre-cats went to hell and dumped into it. I've had no problems without it, although I dont have inspections here. 06, 4.0
Same here.
 
OP
L

Long Rider

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Your pre-cats are necessary because there tied into the ECM.
The 3rd cat is not, I deleted my 3rd cat when my pre-cats went to hell and dumped into it. I've had no problems without it, although I dont have inspections here. 06, 4.0
Was there much difference in sound without the third cat?
 

Rubicon88

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It's technically a federal law tampering with any of those...

I don’t know the inspection law in your immediate Texas area but if you choose to sell it you absolutely better let the new buyer beware of what you removed as it could cause them a major PITA if their area checks those things.
 
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TheBoogieman

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Can I bypass the last catalytic converter on an 05 Rubicon? The primary cats died on my TJ. I ordered Magnaflow primary cats and manifold, but cannot afford the last or secondary cat.
I replaced all three on my 05' for just over $300 and I've also bought an inexpensive universal cat for the rear one. We have to have them here in Va to pass state inspections, so removing them wasn't an option for me.
 
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TheBoogieman

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I got rid of my cats.
Mine died slowly.🤫 We share the same bad habits.


badcat (2017_11_20 00_38_12 UTC).jpg
 
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KingCarGuyZ

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Any performance increase from removing the 3rd cat? On one of my older cars it was a popular mod to increase power.
yeah, it's not gonna make a real difference, if you wanna remove it for sounds or just cause there annoying, then go ahead. but performance there's no point, manifold and pre-cat's are more restrictive. not to mention the exhaust ports on some of these years.
 
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TheBoogieman

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No.
Unless its clogged the performance is only psychological.
No No No. Bad emissions equals a Covid outbreak and pollution worse than vaping. :rolleyes:Unless you're voting for Kamila Harris for President......Oops.... I mean sleepy Joe for the first 6 months. Oil will be phased out is what he said. Thank God the electric Wrangler is coming out for the GREEN RAW/New DEAL IDIOTS!
 
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Rubicon88

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No No No. Bad emissions equals a Covid outbreak and pollution worse than vaping. :rolleyes:Unless you're voting for Kamila Harris for President......Oops.... I mean sleepy Joe for the first 6 months. Oil will be phased out is what he said. Thank God the electric Wrangler is coming out for the GREEN RAW/New DEAL IDIOTS!
T R U M P

All

The

Way

!!!!!!!!!!!!!!!!!!

Thank you,

Drive thru
 
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KingCarGuyZ

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No No No. Bad emissions equals a Covid outbreak and pollution worse than vaping. :rolleyes:Unless you're voting for Kamila Harris for President......Oops.... I mean sleepy Joe for the first 6 months. Oil will be phased out is what he said. I guess that electric wrangler is looking like a super expensive option right now.....NOT!
The Green RAW Deal Is committed to 100% renewable energy by 2030, costing $200 billion per year. It would create a Renewable Energy Administration to create up to 20 million new green-centered jobs. That would cost $400 billion a year. No tax increases either. BS bad politician.
T R U M P

All

The

Way

!!!!!!!!!!!!!!!!!!

Thank you,

Drive thru
How does that have anything to do with catalytic converters?!? can we keep the political discussion in the political forum?
 
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