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solidONE · 09-04-2021, 11:59 PM

I started to get some pretty wild fluctuations in my commanded AFR and AFR after reverting back to factory, then reinstalling long tube header. Switching out the O2 sensor doesn't seem to effect it. It would still have these fluctuations even with brand new O2 sensors.

This behavior seems to effect the idle as well at times, causing the rpm to dip and engine to cut off. What would cause the commanded AFR behave this way if it was not a faulty O2 sensor? Misfires? Exhaust leak at the headers? Has anyone seen this kind of thing before?

https://datazap.me/u/solidone/afr-fl...8076&mark=7744

https://datazap.me/u/solidone/afr-fl...7616&mark=7744

09-04-2021, 11:59 PM	#17
solidONE Senior Member Join Date: Dec 2012 Drives: FR-S Whiteout Location: California Posts: 2,863 Thanks: 1,808 Thanked 791 Times in 611 Posts Mentioned: 42 Post(s) Tagged: 0 Thread(s)	I started to get some pretty wild fluctuations in my commanded AFR and AFR after reverting back to factory, then reinstalling long tube header. Switching out the O2 sensor doesn't seem to effect it. It would still have these fluctuations even with brand new O2 sensors. This behavior seems to effect the idle as well at times, causing the rpm to dip and engine to cut off. What would cause the commanded AFR behave this way if it was not a faulty O2 sensor? Misfires? Exhaust leak at the headers? Has anyone seen this kind of thing before? https://datazap.me/u/solidone/afr-fl...8076&mark=7744 https://datazap.me/u/solidone/afr-fl...7616&mark=7744 __________________ Intent > Content cowardice is the mother of cruelty.