Pablo

iTrader: (1)

im looking at this table and wondering if it means. Just as a guess is it what the iac will be at as a base setting and only makes changes from that to adjust for varying conditions? because i went to set minimum idle and set it 50 rpm under the target rpm in my chip
when when i got the car running it seemed to be struggling to hold that low of an rpm (the target) and eventually just creeped up to a couple hundred rpm higher than what i set as minimum idle (50 rpm under target idle)
as far as I understand its optimal to keep the iac steps to a minimum, so should i try decreasing the table across the board by about 20 steps? (this would make the warm idle about only 4 idle steps on the iac)
Ive allready modified my IAC pintle to be a little quicker reacting

Anyone out there know?

if not i guess ill just try it out and play with it to see how it works

Pablo

iTrader: (1)

BTW i corrected the high idle by setting the minimum idle rediculously low

FastBroker

Pablo, I think I already told you that that table is for NON-IDLE operating conditions, ie, under cruise. IAC motor will go wherever it has to go when you are in the idle loop to get the programmed (in PROM) idle speed ("target idle vs coolant" table),

Did/Can you call Traxion to get my number to call me???

Pablo

iTrader: (1)

no i didnt fast, got icq? shoot me an email

ok so if thats the case, why was my idle 700 rpm with the IAC pintle zeroed out, and ran only a few seconds at that low when the car was started and slowly crept up to 1100 rpm and just looking at the pintle its somewhat retracted at idle despite the high idle
its almost as if the pintle wants to be at a prescribed amount of steps. Also, hows the IAC steps vs coolant determine you are at part throttle? is this soley off of VSS signal.. I.E. off 0 mph? then what about deccel in neutral (manual tranny)
and what is IAC in park or neutral offset? (thats the ecm constants section)

Pablo

iTrader: (1)

that doesnt make sense, why would the pintle want to retract a prescribed amount for part throttle operation?

FastBroker

I wouldn't asy it retracts, I would say it "parks" at the value in the table so that the ECU can make calculations/AFR iterations (like integrator/BLM work) that do not include the changing airflow from a moving IAC. Is is an "idle air control" control, not much else... And it doesn't just do it for part throttle operation, I believe it is for ALL operation greater than a few degrees of throttle and when you are not in idle PID loop. ie, part throttle, mid throttle, WOT. It will add a dashpot effect upon quick throttle closing situations and other idle control stuff (to keep engine from stalling) if moving a little (VSS controlled) before ou actually stop your vehicle.

[This message has been edited by FastBroker (edited September 20, 2000).]

Pablo

iTrader: (1)

yeah thats what i meant, parks

why does it seem to be parking at several steps beyond zero to where the desired idle speed is not being met despite setting minimum idle below desired idle speed? doesnt make sense to me it must have 'park' value
also, as i understand it, desired idle speed is much much more than an IAC command, the computer juggles timing, fuel, and lastly IAC to meet desired idle speed
I think al lthe other parts in the equation have prescribed settings and obviously the ecm has room to change them (I.e. timing, and fuel) it would seem to me that IAC would also have a base setting that can only change by a certain percentage (just like timing and fuel)
But i dont know.. all i know is that despite a high idle caused by too much iac opening the iac did not decrease its steps in my situation despite minimum idle being set well under desired idle. It almost seems like the timing and fuel requirements are being met (which is why i could set the minimum idle at 700 there abouts) but the iac is not
your thoughts?

FastBroker

If you have an artificially high idle rpm, you may have vacuum leak. Are you using a scantool?

If you set min idle really low (closing the throttle blades, low TPS%), your IAC will have to open a lot to hold your idle rpm because the air cannot get by the throtle blades. Conversely, if you set min idle to 725 rpm, your IAC will barely be open to hold that 750 rpm, get it?

Pablo

iTrader: (1)

You dont understand what im saying

and no i dont have a scan tool, thats a waste of time with my baud rate,
and no i dont have a vacuum leak

I can set minimum idle to 700 rpm, and even lower, low enough to stall the motor so NO i dont have a vacuum leak

with the IAC disconnected using minimum idle set procedure, the idle can be 700 rpm (a bit choppy its a big cam)

shutting off the car, reconnecting the iac, idle starts off at 750 and slowly climbs to past 100
IAC is obviously at more steps than zero because i can see it at beyond zero and the idle is not swinging
there HAS to be an IAC base amount of steps for idle, and i think its the temp vs iac which i will try a little later

[This message has been edited by Pablo (edited September 20, 2000).]

FastBroker

I am telling you Pablo, the scantool will be invaluable to you with this problem even though the baud rate is slow, trust me. Beg/borrow or steel one. You'll be able to see RPM/IAC and MAP values and even if it's only every second or so, that's enough. Most important to this problem will be IAC movement and MAP values... RPM is nice, too.

I'm assuming you are closing the IAC (IAC count = 0) before you set minimum idle, right? Not just disconnecting the IAC connector...


Can you call me???

[This message has been edited by FastBroker (edited September 21, 2000).]

Pablo

iTrader: (1)

dude you talk to me as if im wet behind the ears when it comes to efi.. when ive been playing with chips for nearly a year now, I allready told you i set minimum idle

and i was right, IAC steps vs temp does control idle speed i cut the steps down by 20 and now its idling at a solid 850 rpm, im gonna cut off a few more steps and get it down 100 more. The ecm uses this table as a base setting and allows for a % change to achieve desired idle sort of like blm no doubt

and no i dont NEED a scanner to see map values, rpm, and IAC. For us simple folk, a vacuum gauge will do as will an inductive tachometer, at this point, IAC counts are sort of a moot point, the fact taht it is above minimum idle means the iac is above zero steps

Pablo

iTrader: (1)

btw i would call you but the phone isnt in my name here and that person would get pissed seeing a long distance call on the bill (mom)

get icq and we can chat there if you like, my number is 11291690

Pablo

iTrader: (1)

also, i might add, there is no problem here
the car idled fine before and idles fine now, i just wanted to close down my iac counts by setting minimum idle to 700 and only using the iac to bring it up 50 rpm or so to give a bit cleaner idle
what ive done so far seems to be working as i now have a very steady 15 inches whereas before it was fluctuating between 15 and 14

[This message has been edited by Pablo (edited September 21, 2000).]

FastBroker

I understand what you are saying but what is the Idle Speed vs Coolant Temp table for,then??? Are you saying that if you have for idle SPEED set to 525 w/your existing settings you will still idle at 800? Guess I'm learining, here.



[This message has been edited by FastBroker (edited September 22, 2000).]

Pablo

iTrader: (1)

hey ed i just called but the secretary said you just stepped out for a few minutes, let me know when to call back

FastBroker

Back now. Had to get some soup to cry in...