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Tuning vq35de with uprev

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Just a quick question.

I'm road tuning my car like I have with many other nissan vehicles but I'm running into a problem that I'd like some info on. I set my injectors up as per the data sheet (id1000cc) set my fuel comp maps to 100 to adjust my STFT as I drive along. I usually use this as a reference to scale the maf sensor afterwards. My problem is that my stft don't go back to 100 after making changes on the fuel comp map. For example, if my fuel trim reads 87 at 2k rpm, when I correct it on the fuel comp map and hit enter nothing changes and the stft don't even out. So I'm wonder is this a vacuum leak after the maf sensor or is there something I'm missing completely?

Thank you in advance

How afar is AFR off from target? You may be at a trim min/max value and it cannot go any further, so it will remain at that trim value until AFR is on target with less trim required.

Being that far off target may be caused by items you mentioned like a leak or MAF issue, or other issue.

Also, since you mentioned ID1000cc, they haven't sold those in years. Are you confident they're old ID1000 or ID1000x, and not ID1050x or ID1050XDS? They have pretty drastically different characterization data which have a big impact at low pulsewidths.

Another potential issue is having the o2 sensors swapped on the opposite banks.

Sorry 1050s, the afrs are not off by a lot 14.5-14.9 @ 14.7 target. I'm assuming you mean the rear o2 sensors?

I was referring to people installing the front o2 sensors in the wrong banks. It's a common issue on that specific engine and it causes extreme fuel trims like you have, so worth checking.

Fuel trims are not extreme its just they don't even out (back to 100 on uprev) when making changes to the fuel comp map. This is why I'm stuck normal once you makes changes you see a result with live tuning.

Thanks for your help

Are both banks showing the exact same trim?

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