WOT from low RPM vs high RPM

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secure
Posts: 254
Joined: Tue Apr 21, 2009 7:38 am

WOT from low RPM vs high RPM

Post by secure »

Why fueling differs throttling from low rpm vs high rpm?
I mean engine keeps lean if I WOT from say 2300 rpm to 7000 rpm(14.0 to 12.2)
but keeps rich if I wot from 3700 to 7000 rpm.(12.5 to 11.5)

How do I compensate it?
RICE RACING
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Re: WOT from low RPM vs high RPM

Post by RICE RACING »

Here is an example of it not changing regardless of what rpm you WOT from,
Same gear, same end rpm, one starts at 3300rpm other 4800rpm.
If you are more specific then can suggest what to look at but suffice that there is a stack of things to look at which would influence it and cause you to have different readings.
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secure
Posts: 254
Joined: Tue Apr 21, 2009 7:38 am

Re: WOT from low RPM vs high RPM

Post by secure »

Do you use boost compensation per gear? I actually couldn't find a good log to show. I stopped my last tuning session as I felt some oddness. My AFR is lumpy, jumping 12.3 to 12.7s at WOTs. Logged datas seems fine to me. I decided to flow test my injectors but they turn with good result.

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I may have alternator problems battery is new
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stevieturbo
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Re: WOT from low RPM vs high RPM

Post by stevieturbo »

Why do you think you have alternator problems ? Seems fairly steady to me ?

And what does "felt some oddness" mean ? Certainly a misfire will cause erratic readings, although the rpm trace looks super smooth

Not really following the query though ? And although AFR is a little uneven...don't think it's of any real concern ? Although even loading it up at low boost I'd probably want it a bit richer, and closed loop is inactive ?
secure
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Re: WOT from low RPM vs high RPM

Post by secure »

stevieturbo wrote: Fri Nov 27, 2020 7:28 pm Why do you think you have alternator problems ? Seems fairly steady to me ?

And what does "felt some oddness" mean ? Certainly a misfire will cause erratic readings, although the rpm trace looks super smooth

Not really following the query though ? And although AFR is a little uneven...don't think it's of any real concern ? Although even loading it up at low boost I'd probably want it a bit richer, and closed loop is inactive ?
I'm running E70 and Id1000s are not happy with them in general especially if the car stays so long.
The oddness is lumpy AFR but it is not related with injectors so why it is?
Normally my AFR was super smooth +-0.1 AFR but my latest logs shows around -+0.5 difference.
Okay this may not be a big problem but i think it needs further investigation as it may be a fueling problem per cylinder.
My latest logging data shows 0.359 ms differences @ fuelfinal1.
fuelbase1 seems smooth and fuelmltcll1 is steady at 1.000
So I couldn't understand why it adds-removes fuel at final. I am missing smt or I am paranoia =)

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stevieturbo
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Re: WOT from low RPM vs high RPM

Post by stevieturbo »

Fuel closed loop multiplier stays at 1 because closed loop is off.

If you think some corrections are causing the changes....log all the corrections ?

Does it do the same thing on regular fuel ?

Also a little odd that when it transitions from CL on to off.....the CL target drops to zero ?

Although an extreme representation...fuel base is also fairly up/down for the area shown....so whatever mapping is in those cells could be smoothed a little ?
logger RPM is very stable, logged MAP is very stable...so why is fuel base a little up/down ?
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secure
Posts: 254
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Re: WOT from low RPM vs high RPM

Post by secure »

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I am logging around 15 fueling parameters all seems stable.(except vbat)
I recently changed the injector opening time vbat versus relfp (from ID1000s datasheet)
Interestingly, there seems to be a relation with fuelbase vs. relfp? But normally it should effect fuelfinal??
I should log fuelRelFp1 to see that but it looks like fuelfinal correction is not totally related with vbat.
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stevieturbo
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Re: WOT from low RPM vs high RPM

Post by stevieturbo »

you can have a compensation for relFP.

But relFP is arguably more important than FP...so 100% you should be logging it ( and are logging it )...although you are not logging FP.

For the part of the run you refer to on the S6 log.....battery is pretty solid at 13.9 volts. That is of no concern

However, relFP dropping like a stone on load is a concern. It should be a flatline. So clearly your fuel pressure is also dropping quite badly.
stevieturbo
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Re: WOT from low RPM vs high RPM

Post by stevieturbo »

Holy crap...your relative fuel pressure in that AFR log goes from 4.9bar base down to 3.1 bar under load.

Log FP1.
secure
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Re: WOT from low RPM vs high RPM

Post by secure »

stevieturbo wrote: Tue Dec 01, 2020 12:12 am Holy crap...your relative fuel pressure in that AFR log goes from 4.9bar base down to 3.1 bar under load.

Log FP1.
Good catch. Why I couldn't see it even I'm looking at it. :x
On January 2020 logs show
1.7 Bar boost - relfp 4.4bar to 3.9bar
December 2020 logs
1.2 bar boost - relfp 4.9bar to 2.8 bar :shock:
and inj duty up to %98 :shock: :shock:
there is even 1.50 knock retard but I see them right now.
Good thing is aborting the tuning session with gut feeling = oddness

Ethanol may fuck up regulator diaphram?
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