Still have IAC issues...

[LS1_Dragster]

I got the Holley wired up correctly now, it took some time but it has 4 pins, the 2 outside are one coil and the 2 inside is the other, unlike the stock one. What really helped was going into the bidirectional menu and commanding the IAC up and down. Once it was right (0 = closed air or extended plunger) I got things going pretty good.

Now the problem:

When I zing the throttle the IAC opens fully racing the idle to over 2000RPM, after 5-10 seconds it starts to close and comes back to a normal idle.

I've made so many changes to the tun I dont know what's up or down. Can someone help with this? I just want a little IAC action when I zing it so it wont die after a burnout otherwise it's just there for cold startups.

Keep in mind this is in a dragster and I've tried to eliminate most of the correction tables that I could find, epsecially in the fuel and spark, I just want X fuel and X spark at idle and WOT.

[LS1_Dragster]

Boy, this site is dead..... Sometimes I wish I bought HPT.

Anyways, now I've got so it doesnt race when I zing the gas but now the IAC steps go down when I zing it and it wants to die, what a pain.

[ScarabEpic22]

Sorry man, I have 0 experience so far on LSx motors so I cant help. When Im online I check here at least once, usually 2x if Im on for more than an hour or two.

[mr.prick]

RAFIG did not help?
are you still having trouble with the PIDs not showing data?
sometimes you got to wait more than 2 hours for a response.

[Delco]

Boy, this site is dead..... Sometimes I wish I bought HPT.

Anyways, now I've got so it doesnt race when I zing the gas but now the IAC steps go down when I zing it and it wants to die, what a pain.


Man what a attitude , my 5 year old stamps her feet if shee doesnt get immediate attention.

This site is about understanding the hardware not tuning your engine for you.

As a guide have a look at your throttle cracker and throttle follower setttings , trim them to get the desired IAC action.
Do you have a speed sensor hooked up ? if not the PCM is going to have a hard time desiding what idle is and may stall after a big rev.

looking at your VE table I am not suprised you have some issues , engine would guts up with fuel and then run lean.
Are you tuning with a wideband O2 at the track , if so do a couple of 3/4 throttle passses and some driving back on the return road to sort out some of your VE issues as well - very hard to nail idle until the fueling is sorted 100%

As you are learning the software I would suggest you practice tuning on a stock daily driver first before jumping in at the deep end and then complaoning you cant swim , play with a car you can drive around every day and make small adjustments till you understand how it all works.

Most people forget that EFILIVE didnt make the PCM and all the algorithms inside it - that was GM - what they have done is give us a tool to modify the tune and datalog it , and added some enhancments where time and space inside the PCM permit.

Bit like buying a snap on tool kit and then complaining you cant build a motor

[LS1_Dragster]

I tell it like it is! Really, tons of support and activity on the HPT site, they even were offering help even though I dont have their product...

I wont recall my statement but I did come accross as an ass which I'm not, sorry. Maybe the hours of breathing exhaust fumes hurt more then I thought.

When there's answers they are truncated and barely understandable, reminds me of the early days of Unix, the programmer geeks couldnt understand why the general public couldnt understand the code like they did. Your answer proves my point "As a guide have a look at your throttle cracker and throttle follower setttings , trim them to get the desired IAC action" very meaningfull isnt it?

Mr. Prick, no it didnt help. I had to use the laptop to record the pids and the results didnt help. I'll just keep on trucking and once I figure all this out I'll be able to help others just like I do with the Holley commander. The learning curve has been steep with this custom setup fore sure!

[Delco]

I tell it like it is! Really, tons of support and activity on the HPT site, they even were offering help even though I dont have their product...

I wont recall my statement but I did come accross as an ass which I'm not, sorry. Maybe the hours of breathing exhaust fumes hurt more then I thought.

When there's answers they are truncated and barely understandable, reminds me of the early days of Unix, the programmer geeks couldnt understand why the general public couldnt understand the code like they did. Your answer proves my point "As a guide have a look at your throttle cracker and throttle follower setttings , trim them to get the desired IAC action" very meaningfull isnt it?

Mr. Prick, no it didnt help. I had to use the laptop to record the pids and the results didnt help. I'll just keep on trucking and once I figure all this out I'll be able to help others just like I do with the Holley commander. The learning curve has been steep with this custom setup fore sure!

Well I will tell it like it is ,

Would you rather be spoon fed and say put 0.5@3mph , 0.7@6mph etc - it just doesnt work like that you need to work out what your engien wants.

Zero the lot out and then start experimenting and adding small amounts .

Until you get the idle spark and VE right you will be chasing your tail.

Quite a few of us are proffessional tuners so we are never doing to spoon feed you , best to take the advice and learn as thaty is the only reason you have the tools , if you just want a immediate solution PAY someone do come out and do the basics for you properly.

[joecar]

If you want people to help you, you have to show some good attitude.

You're lucky some people decided to answer you regardless of your comments.

GM PCM's are far more complex than the Holley Commander... the learning curve is naturally much steeper.

The more I think about it the more I fail to understand why you didn't just go with the Commander...:nixweiss:...the GM PCM is a bad choice for your application/requirements.

[joecar]

Oh... and this site is not dead... there are many members who go out of their way to share information and advice. :cheers:

[mr.prick]

yes use your laptop there may be an issue with those PIDs.(beta)
try adding half the value of RAFIG in the problem area.
you should shoot for -.03 to .03, it won`t be perfect every time.
it is important to not be overly rich or lean so edit that data out.
what throttle body do you have?
does it have small hole in the throttle blade?
i had dipping/dieing idle before and RAFIG solved it,
and i`ve heard from a few people that desired airflow
should be all you need to change to have a normal idle.
i know you have a unique vehicle but it should still work very similar to stock.

your {B4307} is wacky to say the least
you are commanding a lot of air in that table
are you boosted BTW?
IMO
you should use only the tables that apply to your trans,
AUTO=P/N
MANUAL=IN GEAR

[5.7ute]

You have zeroed out your throttle follower decay which would cause your idle to hang. I would reset these to stock values at the moment.
As Delco has stated you need to get your fuelling & spark dialled in before messing with the rafig etc. Spark has the most control over your idle as the iac valve moves too slow to make the immediate adjustments necessary. For starters find the best timing & afr for idle with the BIDI controls, Then remove a few degrees & put this timing in the cells you hit at idle. This will give you room to make spark corrections to your idle speed by either increasing the spark in the lower rpm cells or using the spark over/ underspeed correction tables.

[5.7ute]

IMO
you should use only the tables that apply to your trans,
AUTO=P/N
MANUAL=IN GEAR

Dont autos use both????????

[mr.prick]

Dont autos use both????????

LOL
DO THEY?
after looking at some auto bins
i guess they do, but the values differ per side.
learn something new every day.

[LS1_Dragster]

Sorry for being a jerk and speaking out loud, in hind site it was uncalled for...

That being said, I have finally got it to work the way it's supposed to. It took huge changes over stock to get it to come in. When I was making small adjustments nothing was happening so it just complicated things even more.

Yes the GM computer is far more complicated, far more then needed in my opinion. It's just weird how you can have a table that multiplies a table and that table is affected by more tables. It seems that the main table would never be used therefore why have it! Also, the Holley is real time and that helps more then anything. Also, I run them in closed loop at WOT with a wideband O2, cant do that with this.

I didnt go with the holley for two reasons, 1)this setup is cheap and widely available and I felt if I get a handle on it I could use junk yard setups for a few hundred dollars 2)Holley is far more expensive.

When the smoke clears I will create a favorites list and I wont ever have to wade through all the non essential parameters again...

Thanks for all the help.

Lee

[Delco]

Dont autos use both????????


yes they do.

LS1 drag , go to base idle spark and drop the spark at anything above your desired idle speed down , this will force the engine to return to idle quicker and elimiate your hanging as well.

[joecar]

Yes, autos use both P/N and IG.

[joecar]

Lee, I'm glad it's working out for you...:cheers:

The GM PCM would normally have to provide accurate fuel/spark/driveability for a wide range of conditions on several continents, and be able to control/pass emissions on the most strict of those, and monitor itself and its subsystems to detect faults, control the transmission and cooling fans and AC, and provide diagnostics information to a person troubleshooting a problem... there's a lot going in that in that box that can easily be taken for granted.

For drag racing you could maybe use some of those features for monitoring the health of your motor.

Post us some time slips when you get a chance.

Cheers
Joe
:cheers:

[WHYTRYZ06]

Oh... and this site is not dead... there are many members who go out of their way to share information and advice. :cheers:

joe, this dude knows nothing about help..... explain to him what u did for me... oh and btw I could tune his car in a couple of hours...

[WHYTRYZ06]

i could give you the correct pid list and maps, and your idle issues will be gone 4 ever... shoot me a pm ls1 dragster, w/your e-mail addy. and ill see what i can do...

[LS1_Dragster]

Found another issue, the IAC does not park to the commanded park position when the ignition is turned off. Since this is a dragster, when the ignition is turned off all power to the engine is killed not letting the IAC park.

What else will be effected by not having a constant 12v to the computer upon shutdown?

Lee