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O2FB not operating after throttle input.

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Hello everyone,

I am trying to figure this out but am having no luck.

AEM series 2 EMS plugged into a Honda F20c that's installed in a Subaru forester.

Everything works as advertised from cold start till rad fans cycle. However once I blip the throttle the O2FB never turns back on after DFCO. I have checked all of my settings multiple times and even tried changing them to min/max to see if feed back would come back on line. So far I have had zero luck. I contacted AEM and was told my problem is in the "options settings". Well, I have checked every setting I can find. I must be missing something. Please help! I will attach the current calibration if this helps.

Attached Files

Sorry I haven't used the AME series 2 so I can't help you out on this. Hopefully one of our other members might be able to offer some support.

I don't remember many details about the Series2 EMS, all my recent time has been spent with our newer products. Try using Tools >>Compare With Calibration to see differences between your calibration and the AEM base maps. If that doesn't help you find and fix your problem, I can probably dig up some other calibrations to compare against. Be sure to use Help >> Tuning Explanation when viewing the O2 FB tab in the software, the info on the right-hand side of the screen should help explain how the various options interact.

(trying to attach a screenshot of the O2 FB page)

Attached Files

So after some messing around I found out that it was actually my Accel fuel. I went ahead and expanded the decimal place to 0.0000 and found it was actually holding at -0.0008. so it was not able to clear and turn O2FB back on. I think it was to sensitive causing a negative value to be seen on the accel fuel after the throttle was closing? I did not know that this could have a negative value. After adjusting my Accel TPS sensitivity (it was up at 98%) I dropped it to 30%. After a key cycle the O2FB started working once again as advertised.

Thank you for all of the input in to this problem.

Does anyone know why It was seeing a negative value? Am I correct with my theory of throttle closing and high sensitivity was causing it to see a negative throttle position? please correct me if I am wrong

Thanks again

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