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  #16  
Old September 2nd, 2020, 10:58
Black1990jeep Black1990jeep is offline
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Re: High NOX every year

Quote:
Originally Posted by RCP Phx View Post
There is no known physical difference other that the "Carb" number!
Actually the california certified cats are supposed to have more catalyst in them that the 49 state variety. On ones I have inspected, the california cat weighs more, or is bigger. The cost is certainly higher also.

These should do a better job at cleaning up a dirty motor than a 49 state cat. This is very useful at test time.
later model vehicles may have the same cat for 49 states as california, but early ones not so.

at anyrate a new cat and O2 sender are a nice combination to pass the test.
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  #17  
Old September 2nd, 2020, 12:10
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blu3fan blu3fan is offline
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Re: High NOX every year

just for curiosity. I'm gonna only swap plugs and the O2.
I will post the difference.
I already bought the new muffler and cat. it can sit in my pile of parts if not needed yet.
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  #18  
Old September 2nd, 2020, 12:11
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blu3fan blu3fan is offline
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Re: High NOX every year

Plugs are 1year old but my stroker runs a tad rich so she kinda burns plugs.
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  #19  
Old September 5th, 2020, 18:38
Czjeeper Czjeeper is offline
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High NOX every year

NOX is crested at too high of a combustion chamber temperature. How many miles on the engine?
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  #20  
Old September 5th, 2020, 18:54
Czjeeper Czjeeper is offline
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Re: High NOX every year

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Originally Posted by Czjeeper View Post
NOX is crested at too high of a combustion chamber temperature. How many miles on the engine?

Obviously meant created. Forum doesn't let you edit posts?
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  #21  
Old September 5th, 2020, 18:58
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blu3fan blu3fan is offline
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Re: High NOX every year

Nah sadly not lol. I wish.
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  #22  
Old September 5th, 2020, 18:59
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blu3fan blu3fan is offline
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Re: High NOX every year

30k~ on my fresh rebuild from 2016
4.6 stroker.
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  #23  
Old September 5th, 2020, 19:12
Czjeeper Czjeeper is offline
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High NOX every year

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Originally Posted by blu3fan View Post
30k~ on my fresh rebuild from 2016
4.6 stroker.

At my shop, one of the first things I would try is an induction service to clean any carbon off the pistons and valves. If you say itís been running rich, you may have carbon deposits creating hot spots. Another thing to check is your CAT.
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  #24  
Old September 5th, 2020, 20:29
89Mock 89Mock is offline
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Re: High NOX every year

High nox would be running lean. Dump more fuel into it. Try a colder plug. High NOx means low CO and high CO is running rich.

There is a reason CARB puts their stamp of approval on the catalytic converters so I would almost guarantee the 49 state one is different. They have requirements in California and manufacturers don’t want to meet them. Probably because it costs too much money because they want more material in there to reduce emissions.
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  #25  
Old September 6th, 2020, 10:55
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blu3fan blu3fan is offline
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Re: High NOX every year

I cut my old fake flowmater off and the cat does not smell and I can see clearly through it.
I don't think it's shot.

O2 sensor. Change Bosch to NTK
New muffler.
Plugs.
Retest time.
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  #26  
Old September 6th, 2020, 11:03
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blu3fan blu3fan is offline
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High NOX every year

Prior results for reference. Retest will happen Tuesday

Sent from my Pixel 3 XL using Tapatalk
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  #27  
Old September 7th, 2020, 10:00
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blu3fan blu3fan is offline
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Re: High NOX every year

So.
What I learned today.

NTK o2 sensor. I can literally smell the difference. I wish I had a wideband to see. but smells better.

and my fake ebay flowmaster that cost half the real flowmaster.
Sounds 100% the same. no difference. LOL
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  #28  
Old September 9th, 2020, 09:42
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blu3fan blu3fan is offline
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High NOX every year

Soooo close.
Changed o2 sensor. Nothing else yet.

Plugs next then cat

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  #29  
Old September 12th, 2020, 05:29
89Mock 89Mock is offline
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High NOX every year

Definitely going the right direction.

Iím doing plugs on mine. Mine shows high CO at high idle and itís $20 for a new set of Champions.
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  #30  
Old September 12th, 2020, 05:31
89Mock 89Mock is offline
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High NOX every year

CO went up.
NOx came down.

Itís still running a little lean so hopefully the next change works.

Interestingly your hydrocarbons came down.
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