EFIDynoTuning Forum

Got it, thanks.

I believe I set it all up per the writeup, but I'll double check.

And you might be right that it will still update, just take longer.
When I stated it updates every 7 seconds, that's after idling for a decent amount of time....I'm guessing after about 255 seconds. :)

So, I've been playing with manual idle control be keep running into an issue where ISCKAM2 keeps updating, even with UPDATM set to 255.
Looking at my logs, it's about 7 seconds between ISCKAM2 updates.

Any ideas why that's happening?
Anything else I can change to prevent updates?

I'm not able to look at tuning files on this computer, so I can't see you bin or log file.

How much did you change FN1861 table?

I noticed when I started dialing in my startup idle, I had to make bigger changes than I thought (like increments of 0.5) to get noticeable changes in the colder temp columns (100F and below).
I've since been able to make smaller increments now that I'm close to ideal.

I've been dinking around with tuning for a while, but still consider myself a novice, however, even over the last month or so, I've learned a lot of what happens with idle and why and have made huge strides in making my car idle better and more consistently.

What is your DESRPM during that high rpm phase?

I'm running a Tweecer RT with Binary Editor.
I downloaded the latest software from EEC Analyzer site.

I checked again and FN875N is in kg/hr, so I just did the conversion from 0.6lb/min to 16.3 kg/hr. Car starts much better now. Still tweaking the 1861 table to keep IPSIBR close to 0.

So, another question, my car warm idles at about 33 kg/hr. Should I update FN875N to match that, or leave it as is at 16.3 kg/hr (0.6 lb/min)?

Another question, per the Idle Air writeup it states.
FN875N Y-axis to all 0.600

Is that .600 lb/min or kg/hr?

I ask because my calibration/strategy has FN875N in kg/hr.

Further down in the Idle Air writeup in section about SURGING IDLE - PRACTICAL EXAMPLE, there are a few calculations and at the end of that first section, it says to "Put 800 = 0.917 lbs/min in the idle air function"
Note the lb/min comment.

Should my FN875N be updated to be 16.3293 kg/hr (0.6 lb/min conversion)?

I'm working on getting my mechanical idle control sorted out.

What I'm dealing with is startup issues.
I set everything up per the idle air instructions.
Warm idle seems fairly close, maybe a small tweak needed.

Startup is where I'm having issues.
When I start my car in the morning (~60F), the car starts, revs up and then either dies or just barely stays running.

What I noticed is that my ISC duty cycle acts a little odd.
Cranking = 98% duty cycle.
Once car fires and is out of cranking, ISC drops to 17.5% DC and my IPSIBR starts to ramp up (pulling ISC DC up with it).
IPSIBR maxes out at about 0.4 and ISC DC is around 45% and the car runs a bit better as that happens.
RPM is still below DESRPM, but at least the car idles.

Warm start, IPSIBR ramps up to about 0.15-0.2 (somewhere in there) during first few seconds after start and slowly comes back down to 0 after settling in.

What I'm trying to figure out is how much I should be changing FN1861.
I multiplied all rows except the top in that table by 1.2 (i.e. +20%) 2 times and it doesn't seem to change much.
Obviously the values in the table are quite low due to the mechanical idle settings (divide table by 6), so adding that 20% only increases the values in the table by less than 0.1 each time.
Currently, my lower rows are all about 0.5 or below for most columns.

Do I need to bump those lower rows up by a lot more than 20%?
Is there a calculation to determine what values to enter into the FN1861 table based on IPSIBR?
Maybe that's in the idle air or cold start/enrichment writeups, but I didn't see it.