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Sharktuning Question

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Old 05-19-2019, 10:33 AM
  #16  
Ralph Newman
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Default Any luck with this ?

Hi Brian and all,
Can't believe I missed this back in 2017 when it was originally posted. I have had very similar issues for years and finally decided the root cause is senility, pilot error or just low IQ.
Like AO, I have just defaulted to always running open loop but it would really be nice to take advantage of closed loop. So, the big question is have you had any luck with this in the last two years?
Just for reference, I am using Innovate LC-2 and have the WBO2 sensor mounted in the driver's side exhaust and NBO2 sensor in the passenger's. I previously used an LC-1 with same results.
Thanks and I hope all is well, Ralph
Old 05-19-2019, 12:10 PM
  #17  
Speedtoys
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Originally Posted by John Speake
OK, understood. Do you have CO pot "disabled" ?

If you are you are forcing non cat mod I think this means you have been tuning the non cat map. (Where's Jim Corenman when you need him?)

I'm not an expert user and so after 12 years my understanding is a bit rusty.

Maybe copying the tuned map to the other cat map would help.

That's what I do, I tune in the non-cat map, with Force non-cat mode, O2 feedback disabled, CO pot off, and im in the non-cat fuel map.

Then I copy what im happy with to the cat map, and enable everything again.

Old 08-09-2019, 07:08 PM
  #18  
Bulvot
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I'm curious why a faulty narrow band O2 sensor, or wiring, wasn't seriously considered?

One way to confirm that the O2 sensor is the problem is to watch on the fuel monitor page on the SharkTuner to see what the O2 sensor is telling the computer. If it is saying that the AFR is correct, then it thinks that the current AFR is 14.7. If it fluctuates a lot between rich and lean as it stays at the same AFR, it's telling the computer to center on that AFR. If the wideband O2 sensor is properly calibrated (and they do need to be recalibrated regularly), then you should have an accurate AFR from it. If the stock narrow band O2 sensor is telling the computer that the AFR is right, but the actual AFR from the wideband is not 14.7, then you know that the O2 sensor, or its wiring, is most likely bad.

You could switch the positions of the narrow band and wide band sensors to confirm that the situation remains the same. But, if the motor is running well when the narrow band O2 sensor is disabled, then runs poorly when it's enabled, that should indicate that the O2 sensor is the problem, not a difference in the air flows from one side of the motor to the other.

A common failure mode of O2 sensors is to read lean, causing the motor to run rich to compensate for the false lean state. But it's not the only way that they fail. They could fail rich, causing the reverse reaction.



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