86 k5 blazer and 86 v10 suburban emissions help

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86 k5 blazer and 86 v10 suburban emissions help

SoCalSmogGuy
I'm dealing with two 1986 Chevy's, both with 5.7L motors. Two different customers. We are test-only and don't perform repair.

Both customers have had EGR replaced and have new cat's and are still failing for high NOx. Neither have changed their O2 sensor.

Anybody have any similar experiences with these motors? The HC and CO are low but the NOx is 1400 on the suburban (limit ~1040) and 2935 on the k5 (limit 1045).
Work Smarter AND Harder
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Re: 86 k5 blazer and 86 v10 suburban emissions help

kfworry
It could be a few things. The crossover port in the intake manifold could be plugged
preventing EGR Flow. There could be NOT enough exhaust Back Pressure to lift the EGR.
The Water Temperature Sensor on the thermostat housing which sends the vacuum signal
to the EGR valve could be defective. Check Vacuum Hose Routing should be on your
"Trouble Tree".
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Re: 86 k5 blazer and 86 v10 suburban emissions help

SoCalSmogGuy
kfworry wrote
It could be a few things. The crossover port in the intake manifold could be plugged
preventing EGR Flow. There could be NOT enough exhaust Back Pressure to lift the EGR.
The Water Temperature Sensor on the thermostat housing which sends the vacuum signal
to the EGR valve could be defective. Check Vacuum Hose Routing should be on your
"Trouble Tree".
Thank You
Work Smarter AND Harder
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Re: 86 k5 blazer and 86 v10 suburban emissions help

D Rochells 150861
And scope the dang O2 sensors.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

scanner
D wrote
And scope the dang O2 sensors.
Do you think there was any testing before the parts were thrown?   We never got before and after NOx readings.   How are we to determine the course of action the OP should take?  

If the OP could answer what the response time of the O2 sensors are, he should also be able to give us the min/max reading too.    It's all there on the screen at the same time.  
Why make it simple, when it will work equally as well complicated.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

Best Answer I Can Give
 If you read he is TEST ONLY.

 He is doing what all TEST ONLY are GUILTY OF. YES ME INCLUDED.
 He NEEDS. to stop trying to be the NICE guy.

 NOx is a pain in the ass. So many other things can make a High NOx reading.
I have tried to stop. Whats wrong? Sir you need to take it to a licensed shop. "What wrong?" again I tell them, WE ALL SHOULD TELL THEM. All the Test Only people. TAKE IT TO A LICENSED SHOP.

 Stop giving yourself problems and let it be someone else problem.
tired, and just not the tired that sleep can fix.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

scanner
Best Answer I Can Give wrote
If you read he is TEST ONLY.

NOx is a pain in the ass. So many other things can make a High NOx reading.

WE ALL SHOULD TELL THEM. All the Test Only people.

TAKE IT TO A LICENSED SHOP.
Right, when a TO tech posts for help, that's exactly the advice we should give them.  I'll stop asking for information and data from a TO tech.  
Why make it simple, when it will work equally as well complicated.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

D Rochells 150861
In reply to this post by scanner
Probably not. I've given up trying to convert parts throwers, I do ask them why they cats before 30 year old $40 oxygen sensors though. Maybe we need test only, diagnostic only and repair only. The customer is prohibited from seeing the numbers, codes or anything they are tempted to tape up. And we will change code descriptions and part names to Latin. Theres a reason the medical and legal fields keep shit confusing to the average person.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

scanner
D wrote
Theres a reason the medical and legal fields keep shit confusing to the average person.
Right?



Every brother, uncle, and friend is a mechanic and smog tech because it's easy.  
Why make it simple, when it will work equally as well complicated.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

SoCalSmogGuy
In reply to this post by Best Answer I Can Give
Best Answer I Can Give wrote
If you read he is TEST ONLY.

 He is doing what all TEST ONLY are GUILTY OF. YES ME INCLUDED.
 He NEEDS. to stop trying to be the NICE guy.

 NOx is a pain in the ass. So many other things can make a High NOx reading.
I have tried to stop. Whats wrong? Sir you need to take it to a licensed shop. "What wrong?" again I tell them, WE ALL SHOULD TELL THEM. All the Test Only people. TAKE IT TO A LICENSED SHOP.

 Stop giving yourself problems and let it be someone else problem.
You are right. Why can't we both just be heartless tech's like the BAR wants?

All the licensed shops in my area are either rip-offs or R&R mechanics. Gone are the days of diagnosis. I can diagnose EFI with my eyes closed but when it comes to carbeurated or TBI OBDI I don't have a lot of experience.
Work Smarter AND Harder
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Re: 86 k5 blazer and 86 v10 suburban emissions help

Best Answer I Can Give
 Truth Brother Truth.
The problem I have found with the self fixers? They will not listen to what you say. Rather than fight them I just tell them the "Party Line" take it to a shop. Don't like being that way, would much rather help, but if they are not willing to listen to help themselves why bother?
tired, and just not the tired that sleep can fix.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

Kriss Vector
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Re: 86 k5 blazer and 86 v10 suburban emissions help

Kriss Vector
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Re: 86 k5 blazer and 86 v10 suburban emissions help

D Rochells 150861
Of course, it only prohibits test only from repair and diagnosis. Educating the customers is your choice. Repair and diagnosis involve the use of hands and tools, parts throwing by it's nature means not diagnosing. So technically if you tell the customer to replace X on a hunch, you are not breaking the rules. Another example of poor writing by the BAR. Perhaps the next revision will say we shouldn't say anything other than it failed, heres your T+R list and kick rocks sucker.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

Super Star
No no no no no. Never tell a customer to replace parts, unless it's like a gas cap that failed the functional check. That would make you responsible for the car passing smog. Could you imagine the complaint that consumer would give the BAR? "Yeah that smog guy told me my car would pass if I changed this part but he didn't pass it."
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Re: 86 k5 blazer and 86 v10 suburban emissions help

Best Answer I Can Give
It could be just a bad hose to a bad engine. She come s back. "WHAT DO YOU MEAN IT DIDN'T PASS. YOU SAID TO REPLACE A HOSE"

 That about when I stopped.
tired, and just not the tired that sleep can fix.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

scanner
Best Answer I Can Give wrote
It could be just a bad hose to a bad engine. She come s back. "WHAT DO YOU MEAN IT DIDN'T PASS. YOU SAID TO REPLACE A HOSE"

 That about when I stopped.
Of course, it's your fault.  

I had a shop that would send a tech to my shop and ask what possibly could be wrong with the vehicle.  I'd give them suggestion as to what to check.   They would come back and say, we changed everything you said it could be.  They made it sound like it was my fault when the vehicle wasn't fixed.    I stopped doing that, and told them I would check it out, it would only cost them 1 hour of shop time.   They never came back.  
Why make it simple, when it will work equally as well complicated.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

D Rochells 150861
In reply to this post by Super Star
I'm just pointing out another difference in what the book actually says and everyones opinion. It just says not to repair or diagnose. As someone who knows how to repair and diagnose I can tell you that neither involve using my mouth. Unless the flowchart says to curse excessively.
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Re: 86 k5 blazer and 86 v10 suburban emissions help

BasicTech678
In reply to this post by scanner
scanner wrote
Best Answer I Can Give wrote
It could be just a bad hose to a bad engine. She come s back. "WHAT DO YOU MEAN IT DIDN'T PASS. YOU SAID TO REPLACE A HOSE"

 That about when I stopped.
Of course, it's your fault.  

I had a shop that would send a tech to my shop and ask what possibly could be wrong with the vehicle.  I'd give them suggestion as to what to check.   They would come back and say, we changed everything you said it could be.  They made it sound like it was my fault when the vehicle wasn't fixed.    I stopped doing that, and told them I would check it out, it would only cost them 1 hour of shop time.   They never came back.
universal answer for the i can fix it my self guys or just anyone in general who is avoiding a proper diagnosis --

it can be an electrical , mechanical or fuel related problem.

car wont star? it can be an electrical , mechanical or fuel related problem.

car bogs down going up a grade at 55 mph while the radio is on with the headlights off on sundays only?
it can be an electrical , mechanical or fuel related problem

car wont shift properly ? it can be an electrical , or mechanical related problem

check engine light is on? it can be an electrical , mechanical or fuel related problem

basically pay me for diagnosis no i wont give you free answers to throw parts at it and blame me later.
try it basically covers every problem

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Re: 86 k5 blazer and 86 v10 suburban emissions help

Johnnybeme
In reply to this post by SoCalSmogGuy
If you are test-only you also should not be directing customers in any way except to direct them to the nearest test and repair. Explain the failure and move on to the next vehicle.

JM
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