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Old 11-10-2019, 03:13 AM   #41
GreaseJunkie
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No codes anymore, just issues with the readiness of the O2 sensors. Might have to replace those. Check this out, if it will upload this time.

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Attachment 787705
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File Type: pdf Rev Diagnostic Report 2019-11-09 (1).pdf (97.8 KB, 8 views)

Last edited by GreaseJunkie; 11-10-2019 at 03:26 AM.
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Old 11-10-2019, 03:51 AM   #42
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Originally Posted by GreaseJunkie View Post
No codes anymore, just issues with the readiness of the O2 sensors. Might have to replace those. Check this out, if it will upload this time.

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Attachment 787705
Perhaps, but there are some weird things about that diagnostic report. There is no rpm reading and no MAF reading. Was this with the engine runnng?

The long term fuel trims are high at 6% & 7%, but there is no short term trim number.

You need to run a log of the live data from an absolute cold start, with ac off, and let it idle for 5 minutes or so. Don't touch gas, nothing, just start it and capture the data. This might help confirm if the O2 sensors are a problem or not.

Also change the MAF reading so it shows grams / second. It should be reading about 3.6 to 4.0 g/sec at idle.
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Old 11-10-2019, 09:40 AM   #43
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Just to clarify, yet again, the culprit was the MAF ?
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0714,0171: It was the MAF. NOT intake boots. NOT vacuum lines. NOT Fuel pump
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Old 11-10-2019, 10:26 AM   #44
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Yes sir. The SEL went off immediately.

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Old 11-10-2019, 12:22 PM   #45
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I did the cold start; here are the results. I changed the MAF reading's output to grams.
Attachment 787737
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File Type: pdf 0_Diagnostic Report 2019-11-10.pdf (97.8 KB, 9 views)

Last edited by GreaseJunkie; 11-10-2019 at 12:47 PM.
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Old 11-10-2019, 06:30 PM   #46
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I did the cold start; here are the results. I changed the MAF reading's output to grams.
Attachment 787737
That's not a log of the live engine data taken from a cold start and lasting gr 5 minutes, that's just another diagnostic report which doesn't help to diagnose O2 sensors.

You also didn't answer any questions I mentioned.
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Old 11-10-2019, 06:33 PM   #47
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What questions?

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Old 11-10-2019, 06:35 PM   #48
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What questions?

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Read post #42 again.

Follow these instructions to set up OBD Fusion to log live engine data over time.

https://forum.e46fanatics.com/attach...9&d=1489505619

If you attach the .csv file to a post, you will need to change the extension to .pdf to get it to upload.
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Old 11-10-2019, 10:04 PM   #49
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Alright, I compared readings from this report to the last one I posted and they're different, probably because I ran the reports when the car was running this time. Anyway, I don't know what I'm looking at either way. I'm learning, thanks to you guys.

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Attachment 787813
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File Type: pdf rev3-Diagnostic Report 2019-11-10.pdf (97.9 KB, 15 views)

Last edited by GreaseJunkie; 11-11-2019 at 10:04 AM.
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Old 11-11-2019, 05:57 PM   #50
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50 posts on this. Thanks for everyone's help!

To recap: My codes were popping, put a new MAF, codes gone, but O2 sensors aren't ready and my LTFTs are uneven amongst the banks. 6 and 7%. So I'm thinking they're not being unilaterally affected by an air leak, but rather by old/faulty O2 sensors that are not crapping out equally, hence different readings.

I'm off to see the Wizard of O2 sensors. Hopefully I can close down this post! Unless my logic is flawed?

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Old 11-20-2019, 08:30 PM   #51
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Ok folks, I know you've all been losing sleep over this, but I have some excellent news! I replaced the MAF sensor with a cheap brand from Amazon and the upstream O2 sensors with an Acme brand from eBay. I took the old girl for the obligatory cycle drive and my O2 sensors finally readied. Went back to the ol' emissions place and passed. Done and done. Thanks for everyone's help!!

PS: I know, the cheap parts probably won't last very long, but they are doing their respective jobs for now.

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