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Rear o2 causing idle problems?

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Old Apr 18, 2013, 08:52 PM
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Rear o2 causing idle problems?
I've been having issues with afr's at idle only.With everything i checked out it has lead me to believe it's the fic 750cc injectors or maybe o2's.. The front o2 works fine,my trims are within -/+ 2%.But the rear o2 isn't.I keep getting rear o2 heater and rear o2 performance. In my logs i can clearly see it doesn't work.Could that cause the afr dip i'm getting?
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Old Apr 19, 2013, 04:07 PM
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I'm getting the same exact thing you are. I'm about to say **** it and just delete my rear o2 all together. Im on FIC 950's and my fuel trims are +/- 5%
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Old Apr 19, 2013, 04:44 PM
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Rear o2 is only there for emissions purposes, it has no effect on AFR's whatsoever.
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Old Apr 19, 2013, 04:45 PM
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Are u planning on deleting it in ecuflash? If u do that let me know how it works out.
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Old Apr 19, 2013, 04:49 PM
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Originally Posted by Raptord
Rear o2 is only there for emissions purposes, it has no effect on AFR's whatsoever.
What if the o2 has a short inside?
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Old Apr 19, 2013, 05:45 PM
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Originally Posted by TurbosamVIII
What if the o2 has a short inside?
Like I said, it doesn't control anything AFR-related, so no matter what crazy signal it could be sending the ECU, other that throwing CELs nothing else will happen.
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Old Apr 19, 2013, 06:01 PM
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Originally Posted by Raptord
Rear o2 is only there for emissions purposes, it has no effect on AFR's whatsoever.
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Old Apr 19, 2013, 06:22 PM
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Originally Posted by Raptord
Like I said, it doesn't control anything AFR-related, so no matter what crazy signal it could be sending the ECU, other that throwing CELs nothing else will happen.
Ok then. So what do u think could cause my injector duty cycle spike at idle only? Any ideas?
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Old Apr 19, 2013, 06:32 PM
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Originally Posted by ApacheToYaDome
I'm getting the same exact thing you are. I'm about to say **** it and just delete my rear o2 all together. Im on FIC 950's and my fuel trims are +/- 5%
Can u post any logs
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Old Apr 19, 2013, 06:41 PM
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Can you post a log as well Turbosam?
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Old Apr 19, 2013, 08:21 PM
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Originally Posted by Raptord
Can you post a log as well Turbosam?
EvoScanDataLog_2013.04.08_09.54.44.zip
Please take a look and tell me what u can see.
Last edited by TurbosamVIII; Apr 19, 2013 at 08:30 PM. Reason: to add a comment
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Old Apr 20, 2013, 07:55 AM
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Checked your log Turbosam and I didn't really notice any big problems with the rpm during idling, is there any time in particular in the log where the idle was bad?
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Old Apr 20, 2013, 10:45 AM
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Originally Posted by Raptord
Checked your log Turbosam and I didn't really notice any big problems with the rpm during idling, is there any time in particular in the log where the idle was bad?
The problem is that the afr drops at idle only. If u watch the injector duty cycle spikes and i can't figure it out.
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Old Apr 21, 2013, 09:34 PM
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I posted a log. Watch the IDC,it jumps at idle only.Can someone take a look at it and give me some input?
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Old Apr 22, 2013, 07:03 AM
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I cannot see anything in the log you posted. Everything looks to be normal. I did not see wideband in your logs though that may show something.
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