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jetape

Increased VE cell values one day, the next day it shows leaner

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A little confused after my latest tweaking to my VE table, this is on a jetski.

I went out and logged a bunch of RPM steps, at 5k I saw AFR of 13.55 versus target 13.39 so I made a tiny adjustment and added 1 VE point (I expected to overshoot to the rich side a bit)

Two days later I go and instead of seeing AFR drop I see a massive increase.  Even though I increased the VE values in the affected cells my AFR went from mid 13s to low to mid 14s.  What the heck, same effect at other RPM points I modified.

I log fuel pressure and it did not change, the elevation on day two increased by about 150m.  Nothing else in the tune was changed, just a bunch of fuel cells.

Images below show the fuel table on both days, day 1 and day 2 respectively, hard to see behind the cursor on day 1 but the values were 88.2 (increased to 89.2 on day 2) and 89.9 (increased to 90.8 on day 2).

What could be happening here?

weirdafr1.PNG

weirdafr2.PNG

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Thats a VE change of less than 1.5%, i wouldn't think it would change the AFR that much. How good is your wideband setup?

Its always best to attach logs and map than screenshots. 

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2 hours ago, Ducie54 said:

Thats a VE change of less than 1.5%, i wouldn't think it would change the AFR that much. How good is your wideband setup?

Its always best to attach logs and map than screenshots. 

Here are the logs, the weird part is I added fuel after looking at day 1 log ...but it went way leaner everywhere.  I'm using LC2, I've dealt with ground offset and I have it span 0.1-4.9v 11-15 afr so any small differences would be tiny.

Day 1 (first pic): https://www.dropbox.com/s/q7ndo9g9bs5ghav/a6.llg?dl=0

Day 2 (second pic): https://www.dropbox.com/s/lvrssjd5dldb13x/x1.llg?dl=0

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Im having issues getting data from one of your log files. What changed from the first day to the second day in regards to idle AFR? 1st day the AFR was a lot more consistent.

test.thumb.png.9b2e02afa74a4744dd260402f1f6c0fa.png

 

 

 

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Day 2 nothing was changed below 2500 RPM and yeah idle was also leaner for some reason, here are the two maps that logged the above.

 

Day 1: https://www.dropbox.com/s/4p7rjyjir2umgt4/custom18.8.pclr?dl=0

Day 2: https://www.dropbox.com/s/daeukycmffrr72d/custom19.pclr?dl=0

 

Could some kind of a boost/vacuum leak cause the weirdness between the two days?  I did have my intake piping between the intercooler and throttle body out but I'm 100% sure everything went back in tight and sealed, it's only 4 clamps.

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