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Discussion Starter · #1 ·
Hello Fella's ...

Happy Thanksgiving .......

So I have been stuck in the same situation with my car. If you recall, I managed to fix all the DTC/MIL codes thanks to your help .... at this point I still cannot pass emissions as my reader faults the EGR/CAT/O2.

To date, I've changed out the EGR valve and solenoid, along with all four O2 sensors . I partly did the O2 swap because I had the headers recently coated inside/out and wanted to be sure that something else inside hadn't somehow messed with them. I had to be under there anyways and for the cost and little time, I thought it would also eliminate one variable. I also cut out and welded in a new passenger-side CAT. I picked up a constant rattle and every time I looked in that area it was coming from (where the heatshield or that CAT was) I couldn't find any other culprit so again, tried to remove two variables. I removed and added heat-shielding/padding in between the heatshield and body and as mentioned replaced the CAT. Despite all this and now 300 miles of driving, the emissions faults are not clearing.... I think the only thing thats not new is the driver side CAT. Car only has 115K in miles so perhaps its conceivable that both CATS were in need of replacement but who knows.

So anyway... posting here to source out any ideas before I call "no joy" and have a mechanic look at it. I always want to solve myself, so I can learn but after all the work I have done to get it this far, along with enjoying driving her again, I dont want to lose any more time....

Thanks for your help.

Jorge
 

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Are you following the diagnostic flowcharts in the Factory Service Manual for these codes? ...if not, download it and do it right. No guessing.

 

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Discussion Starter · #3 ·
Hello .. and thanks for the response ... I guess this is where I am stuck. Based on my scanner, there are no codes .. no MIL or DTC codes .. no service engine or check engine light .. All my scanner is currently showing are the emission faults mentioned above, which is preventing it from passing smog.
 

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Have you done a running sensor scan with your scanner. It could show you where the problem lies. If you don't have a scanner that does running sensor scans, go buy one.

If you haven't a clue what sensor reading are showing you, let me know and I'll post the pdf file " scanner readings and what they mean". Written by our member Injuneer.

Also, be aware that not only the sensors can cause faulty readings. So can wires, connectors, grounds, power feeds, & splices in the wire.
 

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Discussion Starter · #5 ·
Hello .. thanks for the insight/help .. I have an old Craftsman scanner and honestly not sure if it does or does not.

So in response to your second point - nope .. I have no clue but very willing to learn and understand so yes please post/send the .pdf file. It will help me know if my scanner can do it or not and then direct me to the correct scanner to get ...
Lastly good points. ... your third comment... I had not been thinking about all the other elements involved....

in any case... thank you ....

Jorge
 

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Have you done a running sensor scan with your scanner. It could show you where the problem lies. If you don't have a scanner that does running sensor scans, go buy one.
While troubleshooting my fake MAP failure, I also read that you could read the raw sensor values. Is this what you're taking about?

What kind of a reader would do this? the one I have only reads the codes. I looked around a bit on Amazon but nothing clicked for me to say that particular scanner reads raw codes.

What scanner is good for this?


If you haven't a clue what sensor reading are showing you, let me know and I'll post the pdf file " scanner readings and what they mean". Written by our member Injuneer.
If you could post it, please do. would be good for me too.

thanks
 
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