Hearing an exhaust leak before the CAT

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Hearing an exhaust leak before the CAT

timmy
A friend of mine recently got a smog license. He tells me “hearing” an exhaust leak before the cat is automatic fail. He got this information from the classes he took. I have never failed a car for “hearing” a leak so is this some new rule? I did a search but the results are from 2013/14. Is there a new rule about exhaust leaks or is my friend misinformed?
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Re: Hearing an exhaust leak before the CAT

Lose weight
I hope the instructor did not give him this falsified OPINION. Had a newbie tech work with me sat. Supposedly treat a coolant leak as a fuel leak:fail. BS
From fat to buff. Healthy diet and exercising is not expensive it takes will!
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Re: Hearing an exhaust leak before the CAT

Moderator
This post was updated on .
In reply to this post by timmy
There are no "audible" or "olfactory" inspection results.  I use my ears and nose to guide my eyes, but I only fail defects that I can actually see, and I would challenge the competence of anyone who stated differently.
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Re: Hearing an exhaust leak before the CAT

BlueSky
In reply to this post by timmy
timmy wrote
A friend of mine recently got a smog license. He tells me “hearing” an exhaust leak before the cat is automatic fail. He got this information from the classes he took. I have never failed a car for “hearing” a leak so is this some new rule? I did a search but the results are from 2013/14. Is there a new rule about exhaust leaks or is my friend misinformed?
Your friend is misinformed.
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Re: Hearing an exhaust leak before the CAT

138541
In reply to this post by timmy
Was also told this in an update class I took several years ago by the instructor. Didnt take long before I got a visit from BAR from a customer complaint advising me that I was informed incorrectly.

Funny fact.... Instructor was and still is employed by BAR.

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Re: Hearing an exhaust leak before the CAT

dano
Ask 2 BAR rep's the same question get 2 different answers.
Not the first time for that I'm sure.

If we are to pass substantial pre cat exhaust leaks letting
the emissions out to the atmosphere before passing through
the catalyst and reducing and converting emissions into CO2
why even have the cat then??
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Re: Hearing an exhaust leak before the CAT

nanz1414
In reply to this post by timmy
I asked bar.. about the Honda cats.. the ones built in the front of exhaust manifold.. how they always crack..  he told me not to fail them for the cracks. I even told him.. there was even a recall from Honda.. stating these manifold had a defect...
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Re: Hearing an exhaust leak before the CAT

My Name is Nobody
In reply to this post by Moderator
barrym95838 wrote
There are no "audible" or "olfactory" inspection results.  I use my ears and nose to guide my eyes, but I only fail defects that I can actually see, and I would challenge the competence of anyone who stated differently.

barrym95838
EO/EI/LA/BA144107
Amen!
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Re: Hearing an exhaust leak before the CAT

dano
Put a strip of paper in front of the suspected leak and now you can see
it. If the emissions don't flow through the cat they are not reduced.
The cat relies on the correct amount of absorbed O2 and then release
to cause a adequate reduction of emissions. The real question is does
the leak cause or change emissions that are released to the atmosphere??
I think so. Not to mention depending on the location of the leak in ref to the O2 sensor the CE light may be on for the next smog test.  In the end it is what the BAR says. No matter how anyone looks
at anything or what may be rite or wrong. If that's what the BAR says then
that's what it is. I would rather see it in the manual myself then just hearing
it from a rep and then hearing it differently from a different rep.
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Re: Hearing an exhaust leak before the CAT

Best Answer I Can Give
 last time I checked, we FAIL for what we SEE, NOT WHAT WE HEAR.
 Never make fun of the choices your wife makes. You were one of them.
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Re: Hearing an exhaust leak before the CAT

dano
Best Answer I Can Give wrote
last time I checked, we FAIL for what we SEE, NOT WHAT WE HEAR.
I'm not saying either way about that. What I am saying is it does
change the emissions being introduced to the atmosphere. And
I also have heard different instructors saying that would be a fail.
I have not however asked any BAR reps. their opinion on that.
I have many times had 2 different BAR reps who were asked the
same question give 2 different answers. As I'm sure many veteran
techs here have.

And just for the record Besta. The only advice I would actually go
with from you is where to find the best jelly doughnuts in town.
Rather I agreed with you or not on the subject.  
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Re: Hearing an exhaust leak before the CAT

Best Answer I Can Give
 Don't like Jelly doughnuts. If you are trying to get a rise out of me, Forget it. I have been insulted by better than you. That will be the last time I feed the TROLL.

 The only truth that I have read from you so far is DON'T TRUST WHAT A BAR REP TELL'S YOU.
Show me in the book.

 You are LOOKING for a fault. VISUAL Inspection. When you look to do repairs then YES, you use all your senses to help you fix the problem.
 Never make fun of the choices your wife makes. You were one of them.
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Re: Hearing an exhaust leak before the CAT

BlueSky
In reply to this post by timmy
We should be able to fail for exhaust leaks but there isn't any rule for this.  I've been told that if the exhaust leak is large enough it will set a code for lean mixture or exhaust sample dilution display and the test can not continue on the BAR97.

I had a 2004 Buick Rainier in recently, 5.3l, and both manifolds were leaking.  The vehicles computer set codes for lean conditions P0171 and P0174.  Customer replaced the manifolds, drove it for a week and the check engine light turned off on it's own.
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Re: Hearing an exhaust leak before the CAT

none
I had a mid 90s Chevy S10 4cyl. fail for NOx. We fixed the pre-cat exhaust leak at the flex pipe and it sailed through. It didn't set any codes though.
People are usually shocked when they find out I'm not a very good electrician.
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Re: Hearing an exhaust leak before the CAT

dano
none wrote
I had a mid 90s Chevy S10 4cyl. fail for NOx. We fixed the pre-cat exhaust leak at the flex pipe and it sailed through. It didn't set any codes though.

Backpressure EGR???
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Re: Hearing an exhaust leak before the CAT

dano
In reply to this post by Best Answer I Can Give
Best Answer I Can Give wrote
Don't like Jelly doughnuts. If you are trying to get a rise out of me, Forget it. I have been insulted by better than you. That will be the last time I feed the TROLL.

 The only truth that I have read from you so far is DON'T TRUST WHAT A BAR REP TELL'S YOU.
Show me in the book.

 You are LOOKING for a fault. VISUAL Inspection. When you look to do repairs then YES, you use all your senses to help you fix the problem.

I know this is all in text and written so a lot is lost in interpretation. I am not looking
for a rise out of you at all. Just stating a fact that I don't take anything said
from you, even if I know it would be true. Most everything I've heard you say
is just a rant from a cheaters point of view. I don't insult people. I talk shit and
laugh and play to much but not to insult.  

Looking for a fault and doing a repair is one and the same. Using your senses
to do repairs and using collected data and specs. is what separates parts throwers
from repair technician.  I'm sure you have a buddy somewhere to help you find the
problem though...  LoL!!!  
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Re: Hearing an exhaust leak before the CAT

none
In reply to this post by dano
dano wrote
none wrote
I had a mid 90s Chevy S10 4cyl. fail for NOx. We fixed the pre-cat exhaust leak at the flex pipe and it sailed through. It didn't set any codes though.

Backpressure EGR???
NO. With an exhaust leak the pulses pull air in also (especially on a 4cyl.). When you get too much oxygen in front of a catalytic converter it cannot reduce the NOx.
People are usually shocked when they find out I'm not a very good electrician.
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Re: Hearing an exhaust leak before the CAT

dano
none wrote
dano wrote
none wrote
I had a mid 90s Chevy S10 4cyl. fail for NOx. We fixed the pre-cat exhaust leak at the flex pipe and it sailed through. It didn't set any codes though.

Backpressure EGR???
NO. With an exhaust leak the pulses pull air in also (especially on a 4cyl.). When you get too much oxygen in front of a catalytic converter it cannot reduce the NOx.
And since we don't check emissions on 2000 and newer that is why
we should not cert. pre cat exhaust leaks.
I think all vehicles should be ran on the 97. Like quite a few other techs here.
Unfortunately it seems like as soon as they get enough of the older
vehicles off the road they won't justify doing the older vehicles at all
anymore.
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Re: Hearing an exhaust leak before the CAT

none
dano wrote
...I think all vehicles should be ran on the 97. Like quite a few other techs here...
I will play devil's advocate here (or OIS advocate ).

The example I gave was at least six years ago and It was a mid 90s truck that doesn't go on the BAR-OIS anyway.

In 2016 I averaged over 1000 smogs per month. I have one example in over 13 years. At that rate that is one in at least 100,000 smog checks. Hardly worth changing a program for.
People are usually shocked when they find out I'm not a very good electrician.
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Re: Hearing an exhaust leak before the CAT

D Rochells 150861
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