Strange VE Learn Pattern
#1
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Strange VE Learn Pattern
Anybody else get this type of VE Learn Pattern? The lower rpm/MAP cells appear out of synch with the rest of the VE table. Is there something in the bin? Has anyone seen anything like this before? I'm suspecting that Learn is continuing through the DFCO points.
#2
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Car: 92 Form, 91 Z28, 89 GTA, 86 Z28
Engine: BP383 vortech, BP383, 5.7 TPI, LG4
Transmission: 4L60e, 700R4, 700R4..
Axle/Gears: 3.27, 2.73
You're probably close to right, in that it's seing lean after fuel comes back ON, repeatedly, and doesn't spend enough time there with fuel on to learn an accurate value.
You may also (instead) be seeing the effects of not having enough VBATT PW OFFSET. When VE has to compensate for too little VBATT OFFSET, then you see the lowest MAPs having very very high VE, even though it should just be a normal VE number. If you're even just .2 ms off, it will start to show significant strangeness at low VE. Opposite is true too, where if VBATT is too big, the low MAP VE will be very low (which can cause warmup problems, - anything that is % or "AFR" related actually).
You may also (instead) be seeing the effects of not having enough VBATT PW OFFSET. When VE has to compensate for too little VBATT OFFSET, then you see the lowest MAPs having very very high VE, even though it should just be a normal VE number. If you're even just .2 ms off, it will start to show significant strangeness at low VE. Opposite is true too, where if VBATT is too big, the low MAP VE will be very low (which can cause warmup problems, - anything that is % or "AFR" related actually).
#3
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RednGold,
What I don't undertsnad is that I have this RPM/MAP area of the VE curve defined as DFCO. I.E. goes into DFCO at 35.9 kPa and comes out at 45, comes out DFCO at 1000rpm and can go into DFCO at 1300rpm. Why wouldn't Learn ignore these areas? I have the Injector Offset at 732mv but the VBatt Correction Multplier is set for 0 at 14.4 Volts. Are you suggesting that I should raise that? Wouldn't that affect the entire VE table?
What I don't undertsnad is that I have this RPM/MAP area of the VE curve defined as DFCO. I.E. goes into DFCO at 35.9 kPa and comes out at 45, comes out DFCO at 1000rpm and can go into DFCO at 1300rpm. Why wouldn't Learn ignore these areas? I have the Injector Offset at 732mv but the VBatt Correction Multplier is set for 0 at 14.4 Volts. Are you suggesting that I should raise that? Wouldn't that affect the entire VE table?
#4
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Car: 92 Form, 91 Z28, 89 GTA, 86 Z28
Engine: BP383 vortech, BP383, 5.7 TPI, LG4
Transmission: 4L60e, 700R4, 700R4..
Axle/Gears: 3.27, 2.73
DFCO requires closed throttle, so you probably have the throttle cracked a little during those learn points.
You're using a 747?? It's been too long for me to remember how that works on that ECU. Might need to have the multiplier at 1. What does a stock bin look like there?
You're using a 747?? It's been too long for me to remember how that works on that ECU. Might need to have the multiplier at 1. What does a stock bin look like there?
#5
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Dom: past tuning season i have been letting VE-L set my tables. after Rbob saw them he smoothened them. after smoothing they apparently resemble a more realistic table if that makes sense. i will hold that smoothened table as a base and then compare to a VE-L table that i will allow to be created this spring. and then compare. i too had DFCO enabled during VE-L. i just discovered i hade char-canister disconnected but the routine was occuring in my bin. now that is disabled as well. highway mode i think was and is disabled.
hace you considered running OL and using the WB to "create" a functional table without VE-L input? i think i could log with my logworks and create one as it plots A/F vs rpm vs MAP. then compare that to the table that VE-L creates? this does take a few hours of logging!
hey ! the Bears no longer suck!
hace you considered running OL and using the WB to "create" a functional table without VE-L input? i think i could log with my logworks and create one as it plots A/F vs rpm vs MAP. then compare that to the table that VE-L creates? this does take a few hours of logging!
hey ! the Bears no longer suck!
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