I have read your posts on talking about using the isc multiplier or forcing the isc duty cycle and loggin the air to set the idle for cbaza j4j1 users. I have read the posts on eectuning about doing it for the GUFB a9l users. I really don't understand how to do it for the cbaza j4j1 strategy. I am using Binary Editor now also. Could you perhaps describe how you exactly do these methods to set the idle. Or perhaps a screen shot on tunexchange. My car idles well but the duty cycle is very low it is only in the 30s on startup. Thanks for your help. Justin
Attn: Stanger007
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Stanger007
Founding Member
Sure thing man. Idles are a tricky thing. There are a lot of things that have to be right before you even touch the computer to tune. Tuning idle and the transition to idle is the trickiest part of tuning.
First off, no exhaust leaks or vacuum leaks.
Secondly, fueling has to be correct.
Thirdly, your TB and ISC screws have to be set properly -- 0.010" clearance between TB arm and screw then a full turn in to preload the throttle open and then about 2 turns out from bottom on the ISC screw
Now you are ready to tune.
Get the car warmed up and idle it.
Clear the computer's memory.
Log IPSIBR and RPM at idle.
If IPSIBR is 0.35 then go into the Neutral idle airflow function and add 0.35 at that RPM point.
This should get ya started. The kicker is that most people have other issues (the prereq's above) and chase their tail.
There's several other ways to go about doing this but I have found this to be the most foolproof and fastest way to do things after tuning quite a many cars.
Wes
Wes-
I have no exhaust or vacuum leaks. I pull around 18 on the gauge for vacuum. MAF curve is loaded and is accurate according the EEC analyzer; I have the original flow sheet as well that I converted.
So you prefer to set the throttle body with the feeler gauge and not by getting it to idle at the lowest point possible? I am also running a fox style throttle body so no ISC screw to turn.
So when you log IPSIBR and RPM and in your example you get 0.35. You say to add this to the datalogged rpm point in the isc neutral idle airflow function correct? And you also mean add 35% correct? Not the actual 0.35 to for example 1200rpm; am I right on this? Also for the CBAZA j4j1 strategy the correct target for the isc duty cycle is 35% correct? Thanks again Wes!! Justin
I have no exhaust or vacuum leaks. I pull around 18 on the gauge for vacuum. MAF curve is loaded and is accurate according the EEC analyzer; I have the original flow sheet as well that I converted.
So you prefer to set the throttle body with the feeler gauge and not by getting it to idle at the lowest point possible? I am also running a fox style throttle body so no ISC screw to turn.
So when you log IPSIBR and RPM and in your example you get 0.35. You say to add this to the datalogged rpm point in the isc neutral idle airflow function correct? And you also mean add 35% correct? Not the actual 0.35 to for example 1200rpm; am I right on this? Also for the CBAZA j4j1 strategy the correct target for the isc duty cycle is 35% correct? Thanks again Wes!! Justin
Stanger007
Founding Member
In the case of no ISC screw, you can also lock your ISC at 35% dutycycle with some params I added into BE. Set the ISC multiplier to "0" and the ISC dutycycle to "35". Then run your TB screw in or out to achieve the desired idle RPM. Remove the 35% lock (back to 1 on multiplier and 0 on adder) and tune the ISC neutral idle air function from there.
Lotta ways to do this, this is only one method.
I do mean to add (+) the value of 0.35 - it is in lb/min of airflow, not a percentage although I see how I confused you since 35%-40% on the ISC dutycycle is coincidentally about where you should be once all is said and done.
This will get your warm idle acting correctly. Cold startups are related but also a totally different animal.
Wes
Stanger007
Founding Member
I am doing this with the timing spout in correct? When I datalog the IPSIBR it is actually -.22 approximately. So this means I subtract this from the rpm datalogged in the isc neutral idle airflow function correct? I also leave the lock on to do the rest of the isc neutral idle airlfow function right?
Also for inputing the idle in neutral and in gear will be the 122 less than what I datalogged at the idle rpm right? Do I also use the rpm/maf flow data logged with the lock to do the throttle body air flow? Thanks again for all the help. Justin
Also for inputing the idle in neutral and in gear will be the 122 less than what I datalogged at the idle rpm right? Do I also use the rpm/maf flow data logged with the lock to do the throttle body air flow? Thanks again for all the help. Justin
Stanger007
Founding Member
Correct -0.22 means to subtract that mass of air at the logged RPM. Don't worry about the TB airflow scalar as you are "baking" that into the Neutral Idle Airflow function.
For the idle RPM put in the commanded RPM you are after.
If you want to shoot me your tune and datalog I'll be happy to give it a look - [email protected]
Wes
I would send you my tune but I am basically starting over from scratch with a stock j4j1 with the maf curve loaded, egr & smog turned off. For the idle rpm is the commanded data logged rpm you want your idle to be at. What about the one for the idle with the isc that is suppose to be 122 hire than the base?
I guess the way you are tuning is by just adjusting the idle screw once at operating temp to desired rpm. Then going up to 2k rpm doing the isc neutral idle air flow. Using all of this data you adjust it by adding or subtracting what the IPSIBR is. Input data for isc neutral idle airflow and idle in gear and neutral. You are leaving everything else stock settings them I am assuming? Justin
I guess the way you are tuning is by just adjusting the idle screw once at operating temp to desired rpm. Then going up to 2k rpm doing the isc neutral idle air flow. Using all of this data you adjust it by adding or subtracting what the IPSIBR is. Input data for isc neutral idle airflow and idle in gear and neutral. You are leaving everything else stock settings them I am assuming? Justin
Stanger007
Founding Member
You're getting there but I think you're crossing up how EECAnalyzer sets up the idle and one of the methods I use.
What I do is get the TB/ISC to factory specs and then tune the calibration to properly handle the idle under all conditions. There's a good many more tables/functions that are involved than the ones we've mentioned thus far but these are the primary ones you'll want to tune in.
Wes
What I do is get the TB/ISC to factory specs and then tune the calibration to properly handle the idle under all conditions. There's a good many more tables/functions that are involved than the ones we've mentioned thus far but these are the primary ones you'll want to tune in.
Wes
I have success. I used your method and it idles great. I am still getting around -0.04 on the IPSIBR. My ISC duty cycle is around 38-40% now; I have never seen it that high before. You said that 35-40% is where I want to be correct? Wes I can not thank you enough for all of your help!!!
Can you explain your method of creating the timing tables? I viewed your template for hot spark settings and you don't 55 the alt tables and bdln. Can you tell me how I am supposed to set them up since it is different from cal-edit. Justin
Can you explain your method of creating the timing tables? I viewed your template for hot spark settings and you don't 55 the alt tables and bdln. Can you tell me how I am supposed to set them up since it is different from cal-edit. Justin
Stanger007
Founding Member
Glad to hear the idle is improving, continue working with it and make note of how warm and cold starts do and refine it. Congratulations on making it this far, idle tuning is the most difficult part.
To keep things simple I make the three full-sized tables identical and on the fourth smaller table I will set it similar or slightly higher than the rest.
As for finding the best spark to run, well that is a lot of experience and where a loaded dyno really comes in handy. Iron headed cars usually end up in the upper twenties for spark and aluminum headed cars low to mid 30s. Things like head design, fuel octane, compression and many others play into how much spark you can run and where. If you get to a dyno, the tuner there should be able to guide you on these adjustments.
Wes
Stanger007
Founding Member
Correct the ISC Neutral Idle airflow function, this gets you where you need to be 99% of the time.
See if the car is running too rich - if so and your fueling is otherwise matching the commanded then pull some out from the startup adder table.
Also look at bumping some air into the startup idle airflow table at the temperatures you have the problem.
Wes
Stanger007
Founding Member
Check FN1862N/FN1862D for startup air in Neutral/Drive (autos only).
Fueling at startup is FN1361.
Wes
Fueling at startup is FN1361.
Wes
See if the car is running too rich - if so and your fueling is otherwise matching the commanded then pull some out from the startup adder table.
Also look at bumping some air into the startup idle airflow table at the temperatures you have the problem.
Wes[/QUOTE]
Those tables are kind of confusing can you elaborate some more on them. It really does not matter what the temp is. Mostly does it when it's cold. Or am I still battling getting a correct isc neutral idle air flow function. Idles pretty good everywhere else. Thanks, Justin
Also look at bumping some air into the startup idle airflow table at the temperatures you have the problem.
Wes[/QUOTE]
Those tables are kind of confusing can you elaborate some more on them. It really does not matter what the temp is. Mostly does it when it's cold. Or am I still battling getting a correct isc neutral idle air flow function. Idles pretty good everywhere else. Thanks, Justin
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