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Momentarily lean on initial throttle ....

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Old Jun 1, 2016 | 04:45 PM
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Default Momentarily lean on initial throttle ....

Running ESL with AFR gauge always reading etc , when cold it's worse but on initial throttle load in say 4th gear my gauge always goes lean for a mili instant to around 18 On the gauge then back to a normal reading , I've tweaked this and that but no change , when car is warmer it only leans to around 16 on partial throttle at light load in 4th then goes back to normal

Could it be MAF scaling ?

Apart from that I can't work out what it could be as its all out of my conyy really running in closed loop

Cheers
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Old Jun 1, 2016 | 04:55 PM
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If it's only a millisecond then will this just be lag time for the gauge to update?
As the injectors close when lifting the throttle.
Would a free air calibration improve the lag time?
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Old Jun 1, 2016 | 05:36 PM
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I did think of this, but you can also feel a blip in responce that coincides with the lean reading of 18, sometimes its 19

it only goes this lean from cold and will improve after say, 10 - 15 minutes of driving then it just goes to a normal reading of 16 to 17 for the milisecond or so on the gauge when doing the same throttle work.

Maybe i stay in too low a gear for when its cold, it does it if i stay in 4th and slow to around 20 mph then dont change gear and light throttle at say 1500 rpm in 4th. But its fine when i do this when nice and warm. Hmmmm
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Old Jun 1, 2016 | 06:00 PM
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I would think your re injection table is set to around 1500rpm when warm.
What are your settings when cold? Usually these are set at a higher rpm,have you had a play to see if adjusting these helps in the lower temperature columns?
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Old Jun 1, 2016 | 06:27 PM
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I thought maybe the re-injection was wrong for cold but i have played with the table but still no changes, it gets frustrating after a while lol . You would think reinjection set to come on sooner when colder as in my table for example would help with a richer reading but it doesn't seem to make a difference .

heres my settings


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Old Jun 2, 2016 | 10:13 AM
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Id say its your ar gauge not reacting quick enough. What make is it? I take it its wideband?
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Old Jun 2, 2016 | 11:54 AM
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re-injection would only be when your costing down i think. I'd be more inclined to say injector latency/tip in values but you can't adjust them. If you change the fuel injector scale this would have a knock on effect on the latency/tip in as they are related, I'm thinking if your current values are higher than the actual flow rate of the injectors then you wouldn't be getting enough tip in injection to compensate for the rush of air when the throttle is opened.
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Old Jun 2, 2016 | 01:55 PM
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Originally Posted by bludgod
re-injection would only be when your costing down i think. I'd be more inclined to say injector latency/tip in values but you can't adjust them. If you change the fuel injector scale this would have a knock on effect on the latency/tip in as they are related, I'm thinking if your current values are higher than the actual flow rate of the injectors then you wouldn't be getting enough tip in injection to compensate for the rush of air when the throttle is opened.

Makes sense, my current injector scale is 0.85 on yellow 440`s , this setting allows for pretty close AFR readings to actual AFR table within ESL.

i could lower the injector scale to say 0.83 and see if this helps richen it up without hopefully putting the AFR gauge readings out i guess ?
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Old Jun 2, 2016 | 02:21 PM
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worth a punt, if your still running maf based it may be worth trying mafless (are you running a front mount by any chance?)
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Old Jun 2, 2016 | 03:04 PM
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yeah, will try slight injector scaling changes and see if it helps.

yeah im maf based now and no front mount, i was mafless but removed the resistor etc so its a pain going back mafless lol just to test.

im running an induction cone tho that does get good cold air :-)

cheers guys
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Old Jun 2, 2016 | 03:22 PM
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oh no i wasn't thinking about cold air, I was thinking about MAF lag but it would only be possible if you had a frontmount with all the extra piping to worry about. If the injector scale helps it out then what FPR are you running, standard one or adjustable.
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Old Jun 2, 2016 | 03:40 PM
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ok. will adjust the injector scale and see what happens, im running standard FPR Currently

cheers
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Old Jun 4, 2016 | 09:52 PM
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Adjusted injector scale to 0.82 , made things worse , fuel trims in affected low load went to 93

Then changed to 0.87 to test , even worse , fuel trims 90

Thought sod it , tried 0.80 , fuel trims haven't changed but AFR gauge was way out

Now back to 0.85 and hopefully fuel trims correct if not will reset ecu

So injector scale a no no , maf sensor clean and working , not sure what's left to change that would be relevant , sob sob

Could it be the FPR ?

Cheers

Last edited by The Rig; Jun 4, 2016 at 09:58 PM.
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Old Jun 5, 2016 | 01:18 AM
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had same issue from day 1 when i was running esl, went another route so never did solve it, it did it in mafless, maf based, and also on the stock map that came preloaded
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Old Jun 5, 2016 | 08:33 AM
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Lean on application of throttle?
Sounds like lack of acceleration enrichment, increase the ms of accel enrichment for the v/sec where the lean spot occurs.
Alternatively if the engjne doesn't stumble just leave it
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Old Jun 5, 2016 | 08:48 AM
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I would be looking at why your fuel trims jump a fair bit in the area you are having these problems,your trims jump from 93 so pulling fuel out to 103 adding fuel in areas where there is only a small load change (0-5 and 5-7)

I know i have a different setup but to get my trims looking sweet i had to take a fair amount of fuel out(i am maffless tho)

Also notice that your fuel load scaling is different to mine and to stock map in the low load areas,could it be this that's causing the momentary lean?

My load scale is the same as stock all the way to 33.
Might be worth a go at changing your scale at the low load end to see if this improves anything?
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Old Jun 5, 2016 | 09:31 AM
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Originally Posted by ossett2k2
I would be looking at why your fuel trims jump a fair bit in the area you are having these problems,your trims jump from 93 so pulling fuel out to 103 adding fuel in areas where there is only a small load change (0-5 and 5-7)

I know i have a different setup but to get my trims looking sweet i had to take a fair amount of fuel out(i am maffless tho)

Also notice that your fuel load scaling is different to mine and to stock map in the low load areas,could it be this that's causing the momentary lean?

My load scale is the same as stock all the way to 33.
Might be worth a go at changing your scale at the low load end to see if this improves anything?
Speed density will require more acceleration. Enrichment over maf as the extra mass of air inducted can't be compensated for?
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Old Jun 5, 2016 | 09:53 AM
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Originally Posted by boosted
Lean on application of throttle?
Sounds like lack of acceleration enrichment, increase the ms of accel enrichment for the v/sec where the lean spot occurs.
Alternatively if the engjne doesn't stumble just leave it
No option to adjust acceleration enrichment in ESL
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Old Jun 5, 2016 | 10:07 AM
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Originally Posted by ossett2k2
No option to adjust acceleration enrichment in ESL
Not so good
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Old Jun 5, 2016 | 11:37 AM
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Cheers for the input guys, as said Boosted, you cant adjust the variables you mention unfortuantely.

My fuel Map load levels are the same as the Base map i received , i only changed the values from 35 onwards, all the lower load cell values are the same.

It is weird tho how fuel trim lowest load is 0 yet the lowest load in teh fuel map is 4, maybe if i change the 4 to a 0 ? But then i thought these fuel map settings were not really read as the Lambda does all the work at this level ( i dont have closed loop disable )

cheers

Originally Posted by ossett2k2
I would be looking at why your fuel trims jump a fair bit in the area you are having these problems,your trims jump from 93 so pulling fuel out to 103 adding fuel in areas where there is only a small load change (0-5 and 5-7)

I know i have a different setup but to get my trims looking sweet i had to take a fair amount of fuel out(i am maffless tho)

Also notice that your fuel load scaling is different to mine and to stock map in the low load areas,could it be this that's causing the momentary lean?

My load scale is the same as stock all the way to 33.
Might be worth a go at changing your scale at the low load end to see if this improves anything?
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Old Jun 5, 2016 | 12:32 PM
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I wouldn't put a 0 in the lowest load as the 4 covers 0-4 on the scale.

Here's my stock 6s map and my current map,just to show you my fuel map load scale and injector overrun.




Stock




current map
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Old Jun 5, 2016 | 12:36 PM
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How does your boost target look in the problem area?
would lowering the target on tip in help? just thinking if you have a bit too much boost on tip in then this would cause a lean moment?
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Old Jun 5, 2016 | 02:45 PM
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Originally Posted by ossett2k2
How does your boost target look in the problem area?
would lowering the target on tip in help? just thinking if you have a bit too much boost on tip in then this would cause a lean moment?
Surely you will be in vacuum and making no boost at all
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Old Jun 5, 2016 | 02:55 PM
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Originally Posted by boosted
Surely you will be in vacuum and making no boost at all
That's what I was thinking,but the 'pro' map that was on mine showed 0.45 positive boost in 0-24 throttle position all the way from 0-7000rpm
I've now change this as dynamite Duncan made a mess,car drove like a pig and det/over boost like you would not believe!!!
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Old Jun 5, 2016 | 04:23 PM
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Ok guys, cheers, i do have 100% duty cycle where no boost is being made but i chose this as i felt if the solenoid was fully working when it comes to actually needing to work it doesnt need to go from 0 duty to say 71 etc ( But am i thinking rubbish here ?? ) but i found i make much faster boost this way

Heres my current Duty cycles along with an amendment to reinjection,fuel table low cells now back to what they were ( 4 and 6) i did have 100% in the 0 column but have just changed this to 0 as you can see here.




Last edited by The Rig; Jun 5, 2016 at 04:24 PM.
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Old Jun 5, 2016 | 04:26 PM
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Oh and Ossett2k2 , i had to remeber you were running mafless, AFR of 20 lol wow ha :-)
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Old Jun 5, 2016 | 05:34 PM
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Originally Posted by The Rig
Oh and Ossett2k2 , i had to remeber you were running mafless, AFR of 20 lol wow ha :-)

yup 20-17's on idle and closed loop brought my AFR's nicely in line and my fuel trims very close to perfect.
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Old Jun 5, 2016 | 08:11 PM
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Well , no adjustments so far have made any difference , I give up lol

As the fuel trims are in closed loop I guess the lambda is in control and I shall have to put up with it
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Old Jun 5, 2016 | 08:43 PM
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You have for example: 14.7 input into the cell where your fuel trim is out(93) so pulling fuel out.
So say you input 15.7 into that cell then it will not pull as much,if any fuel out,surely the fuel trim will go from 93 to a perfect 100?
Same goes for the cells where you have 106,just take it from 14.7 to 13.7 for example.

I know you can't turn off closed loop but it shouldn't matter,if your ECU is jumping from taking fuel out to adding fuel in such a small load change then I would have thought this would cause a problem?
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Old Jun 5, 2016 | 09:08 PM
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i think this could maybe be a scaling issue, as there are no tables to adjust accel/tip in and coolant temp enrichments then i assume the ecu will be using subarus stock tables, which will mean any scaling will have to be very close to what a stock ecu expects to see,
like i said i had the very same issue and could never get it any better and had spent so much time on the map that i didnt want to touch the scaling again, to mess up my fuelling and having to start over, so just had to live with it untill i went a differant route
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