Jordo, thats how it is in a bunch of other ECUs I've played with. I would expect this one to be no different. I have not tested out that fact but I would be very surprised if this one did something other than the Bosche/Delphi ECUs I have played with.

The double O2's could most definitely be the issue and right now thats the next thing I am going to do (been a bit busy as of late so I haven't played with the car at all as of yet.

I do have larger injectors and the K multiplier was changed accordingly. Even if that wasn't dialed in properly you would just see that in the correction factors as well as at WOT you would go lean or rich depending on how far out your K factor is. Essentially any of those changes will absolutely affect the AFRs but under closed loop the computer will do its best to account for any errors in the tune itself and if your to far out you will get lean or rich bank codes.

Tomorrow I am installing CJMs fuel return system which will warrant a full redo of the fuel tables so I will be playing with UpRev alot then. As I type this I am soldering together my own device for listening to the knock sensor with headphones that they have posted on their website. :tiphat:

:tiphat:

To anyone following this thread unplugging the O2s fixed the trim issue. The car is now doing a much better job at meeting its targets. Haven't had extensive time on it yet, but it does seem to be much better.

That makes me sad. How am I supposed to pass emissions testing if I have to disable my O2 sensors to get the car to not flip out?

Serendepity solved this one for me.
 

Not sure if this issue is still circulating about the forum. I was having the same issue. Bank 1 and bank 2 were always off by 0.5-0.7. An accidental wipe of my rom file lead me to this series of adjustments which virtually eliminated the disparity.

1) I downloaded a different rom from uprev by accident. I flashed the 2013 370 NISMO file 1A40D instead of the one my ecu was supposed to match:1A39D.

2) I began running all uprev programs as administrator.

3) I edged up my injector latency value at 14V a bit (added 0.3ms).

That's it. Like the majority of useful medications on the market, this was a serendipitous discovery. I hope this helps at least one other person.

Peace.
-JMC

unplugged the secondary or the primary -- I'm guessing the former?

Your point 3 might be the reason you're not seeing this happen anymore. Are both your secondary O2s on the same bank?

Secondary, they been unplugged all summer with 0 issues.

This is on my todo list for the V1.75 upgrade. Bought the plugs to be able to pull them completely!

yeah.... i been lazy... :rofl2:

Reading this thread I am looking also in my engine a little differences between banks: 0.5-0.8 AFR, but only in 1800-3600RPM Full Load area!

In this case, it's better to tune all richer maintaining all Bank1 & Bank2 MAX AFR below 12.7, or I must consider a mid value?

...after 4000RPM everything the AFR was balanced...

Some positive feedbacks removing the O2s?

Thanks.

The two banks are pretty close, but in the 3250RPM area, there is a difference :confused::confused:

Two examples:


http://www.psm1999.net/images/share/1diff.png

http://www.psm1999.net/images/share/2diff.png

....mmh! I know.... :tiphat::tiphat:

My question is:

If you have an AFR balanced on the entire range, but only around 1800-3600RPM Bank1 differs from bank2....

What do you do? ....disconnecting O2s (The lambda after the cats) is the solution?

Hmm that is strange.

Here's a silly question, but is your MAF voltages during that area? Wonder if it's possible that the MAF's are reading slightly different from one another?

Interesting!

....this weekend I can try to swap the 2 sensors....

Try it and report if the AFR dip changes between the banks.

I would also double check to make sure you don't have any vacuum/air leaks post MAF. I would imagine a vacuum leak on a MAF based system could make things run funny.