Working on my idle tune

[blsnelling]

I've been working on my idle tune for the last few days. I've finished the Calc.VE tune. I've also followed the Tuning Tutorial and done one round of RAFIG adjustments. I'm still getting surging at times where the truck will eventually die. This will happen if I'm setting idling, bump the throttle to move forward a little, and then let off. Anything obvious in my tune?

My Modified_02.tun

[WeathermanShawn]

BLS:

I should probably give someone else a chance to help you out..especially with an Auto Trans.

You might review your B5934. Those are some wild numbers. That might be wrecking havoc with your spark.

Perhaps someone with an Auto trans will help out. They are definitely tricker than the Manuals..

Good luck..

[blsnelling]

I didn't want to clutter up your sticky thread any more

B5934 - Those are the numbers that came in my tune, except for B4505, which I changed per the Tuning Tutorial. I'm going to set all of these to what SSpdDmon has in the Tuning Tutorial.

Here's the tune with B5934 setup like SSpdDmons. My Modified_02.tun

[WeathermanShawn]

Like I said I do not have much experience with Auto's, but here are some general questions/pointers.

1. Does it happen at all ECT's.
2. What Vehicle Speed does it occur at.

Without starting a whole new Tutorial, you can log up to 24 channels on EFILive. If you pick as many Spark and Idle Pids (TC,TF,etc..) then you can isolate the stall/surge according to which Table is in effect. For example it could be stalling when you switch to the High-Octane Spark (not enough), or you see the TF Air go to zero..

Thats all I have for now. Hopefully we can get some Auto trans guys to help out...

[DrkPhx]

Do you have a log you can post? What are the mods? The spark values in the idle region of the spark high and low octanes tables are wacked out and don't match the spark in gear values. Also the idle underspeed and overspeed values should be changed to help minimize the swing.

[blsnelling]

I did bump idle spark values, as advised by Shawn. Maybe I didn't do it right

I'll have to get you a new log, since there are changes since my last log.

Here's my setup.

'01 GMC Sierra ECSB 4x4, '04 6.0L LQ4 Shortblock, 243 Heads Milled .035 11:1 Compression, Mild Hand P&P, Pac 1218 Springs, Yank PT3200 Stall, Comp Cam 220/224, .581/.581, 112+0 LSA, LS7 Lifters, Melling HP Oil Pump, TBSS Intake Manifold, Edelbrock 3864 90mm T-Body, Doug Thorley LT Tri-Y ceramic headers, Flowmaster 50 SUV, LS1 e-fans, Airaid MIT, Complete valve body build up, 4.30:1 + Detroit TrueTrac,
33/12.50-17 Tires.

[WeathermanShawn]

BLS:

It all depends on what Spark table is controlling at the time. If you have the Throttle engaged and then release it..and it stalls..You might have transitioned from High-Octane Spark to either Base Spark in Gear or Park/Neutral. If you have encountered KR recently, it could even be referencing the Low-Octane Spark.

As I have written "Idle Tips and Tricks", I am purely covering Idle ( 0.0 MPH, 0.0 TPS) and not the many complex transitions from Throttle to Idle.

Normally, one might first construct your High-Octane..then construct Low-Octane. You might then construct Base Spark in Gear with the Spark Mods mentioned in the Tips & Tricks, copy that Table to Park/Neutral. The whole goal is not to have your Spark rapidly change with TPS, but still be in that 22-26 degree range when you are solely at Idle.

Without logging all the Spark and Idle Pids necessary it is somewhat a guess as to what is happening with your Spark and Air. If your Spark is dropping rapidly and too low..you will stall. If your fueling goes too rich..you will bog and then stall. If you are too lean you will surge..then stall. If your Airflow is too low and drops off too rapidly..it will stall. If you Airflow is too high, your Idle will hang.

Now you can see why many tuners do not post their tips on Idle. Every car is different. It is a very tedious procedure. You have to be willing to log all the parameters I mentioned. The Idle Tutorials are all set up to eliminate big swings in Fuel, Spark, and Air.

Try working on the actual Desired Airflow first. If that is right that is 50% of the battle.

Good luck. If you get stuck, post some more logs..

[blsnelling]

Thanks Shawn. I just logged RAFPN after setting all night. I need to add .075-2.00, depending on the cell. I'll do another RAFIG tomorrow morning, and see how they compare. I'll also take a closer look at the different spark tables.

[blsnelling]

Here's my RAFPN log from this morning, along with the modified tun. I added a bunch of pids, but probably won't help much since this was idle only.

My Modified_02.tun

RAFIG_05.efi

[blsnelling]

Base Spark In Gear is now copied to Base Spark in Park, and now doesn't vary more than 3* from High-Octane.

My Modified_02.tun