Johnny_9

If the Ect.c is out, it affects pretty much everything....u should tune that first...assuming u can crank the car the idle map region is well tuned....

Post start is the last thing to address....imho

HRTuning

Post start is added on top of everything else. You need to take into account the differences between when you're cold and warm, like where on the fuel map you're at, the ECT enrichment, etc etc. The more you pull (Negative value) from post start the less fuel will be added and the shorter post start will be active. Watch the fuel value in logging.

raverx3m

iTrader: (1)

wtf. lol

i put post start to zero and it works fine now.

all this **** and a simple solution. i dont know why he put it at 50.

HRTuning

+50? I don't know either. I was under the impression you had -50 since you were trying to pull fuel during cold start.

Boyle.R

@HRTuning, can you create a post start table that is based on ECT?

Boyle.R

Had it idling from 20mins so was up to full temp, AFR was bang on around 14.5 in open loop so don't know why it's adding 15% trim when I enable closed loop. Something to do with VE table?

raverx3m

iTrader: (1)

played with fuel tables a bit and now it cold start at 13.5 and hot restart at 15.8 then drops to 14.5.
with post start set at zero

raverx3m

iTrader: (1)

ok im getting close

i adjusted fuel tables and ect to be somewhat close to 14.7 at idle.

but its still off during post start.


i have cold start at 13afr then it goes to 14 in a minute and stays there to full temp.

but on hot restart it still too lean at 15.8 and 30-60 seconds later goes to normal 14.5 afr.

that is wit zero post start trim.

if i add more fuel via ect tables it will idle too rich during normal idle .
if i add fuel via post start it will startup really shitty and run too rich during cold startup.

pretty much if i add more than 5 post start, the engine starts up like its getting flooded.
with -15 crank trim and zero post start engine starts up ok but not the best.
when i decreae cranking trim even more and zero post start it starts really smooth.

how long does cranking trim last in the system?

raverx3m

iTrader: (1)

Whats the best way to fine tune idle

Anyone have advice in general?

Steps and in what order things should be adjusted.
Cuz im just tweaking without really being able to connect the dots

Boyle.R

Sounds like a post start table based on ECT would sort your problem

HRTuning

Yes, the percentage in that table is only applied during open loop.

I mentioned some time ago to set the open loop "VE" table to 0 in the idle area so there's no change in fuel value when that kicks in.

raverx3m

iTrader: (1)

That table only activates above 126 ect right?
Or is there a delay after start when it activates during hot restart?

I lowered it from 11% to 8% the transition is pretty smoth when it kicks in during warmup.

HRTuning

Above the ECT when in open loop.

That'll help, but going to 0 will allow no change and more control.

If you watch the fuel value in datalogging you can see how these items effect the value.

bigD

I just changed the temp it kicks in at to 0 that way its always using the ve table and there is no transition to worry about seems to work on the cars I have tuned. Wouldn't this accomplish the same thing as just changing the idle area to 0?

raverx3m

iTrader: (1)

why is it set to 126 anyway is that what is set at stock ecu?
im gonna try the zero temp to see how it does

my tuner did suggest to just disable it

HRTuning

Yes. Good idea.

Yes, that's stock.

raverx3m

iTrader: (1)

did that. worked great.

would that be any benefit in building the VE tables correctly for a specific engine?
i know in general what VE table is i just dont understand what the benefit of having it active vs not having it at all.

HRTuning

It's active stock, so that effects the stock tables. You can disable it and tune from there or keep it active and make it work for what you're doing. There's a lot of uses, but it's not necessary to take advantage.

raverx3m

iTrader: (1)

dang. i thought i got it but its still lean during hot restart.(only first 30-60 seconds is lean then it goes to 14.4
i cant increase fuel tables anymore because its already idle at 14.4
and if i increase the post start its gonna get out of whack again.

am i doing something wrong?

what order should all this be adjusted?

HRTuning

Revert to stock settings and try again. Post your setup.

raverx3m

iTrader: (1)

u mean engine? its in my sig.
and stock settings are with 50 post start trim that are too rich at startup.

is post start affected by VE table as well?
the percentage in ve table adds fuel to everything or just maps?

also i just thought about it but Px manifold has the iat sensor on the back of plenum
and most other manifolds have it on one of the runners which is much closet to the engine and gets heatsoaked quicker.

does the iat placement affect fueling?should i do anything to iat fuel table?

btw HRT thanks for help

HRTuning

No, stock was 0. Whoever set it to 50 shouldn't have. I'll assume you have stock injectors since you passed that question off.

You have access to IAT values in logging. Look at the values for a correlation. If you feel IAT correction needs adjustment and you see a correlation go ahead and make some adjustments.

I'll leave you to it. There's enough info here, you have a fairly mild setup, and access to everything you need. There's no reason you can't get this to work properly.

raverx3m

iTrader: (1)

oh i thought i added it in the sig, i have rdx injectors at stock pressure

yes at the moment its set at zero and im keeping it there while trying to adjust the fuel tables and everything else.

and i already set the injector offset i managed to drop the voltage to 11 volts so that gave me enough to set it right.


looking at few logs(cold starts)

original setup with 50 post start it starts 10afr and gradually goes up to 14 afr within 1 minute.

with post start at zero it starts at 12.3 afr and gradually goes up to 14 afr within 30 seconds

and i just noticed the spot where VE tables kick in and it drops from 14.3 to 13.5 afr right at the 126 degree mark on both graphs.(those were done before ve table was set to zero)
so thats been taken care of.
everything else looks good on cold start.

hot restart is for some reason harder to catch becasue its inconsistent.

one time it will be ok next time it starts lean etc.

like all day yesterday it was ok. today it was starting lean. no idea why. cant seem to catch it.

but again it seems like its only for the duration of post start.
even when its set to zero is there a default post start or something?
why does afr change after 30-60 seconds even with post start at zero?
i also changed fuel tables just a lil bit

bigD

keep an eye on your IAT's on the hot starts

Johnny_9

Is there a decay rate for hot start - step 4 in S300. What is your crank pulse (ms) at hot start?