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gpr
September 26th, 2019, 08:16 AM
I need some help with a surging idle. I can't figure it out, and its driving me nuts I have gotten it better but it still is happening. It seems to happen mostly when I'm coasting down to a stop under about 30mph. Once i lift off the throttle and it is returning to idle the afr seems to bounce around.

I think the VE table is good but its odd as sometimes it will be reading a lean afr then another place in the log using the same VE cell its too rich.

Another question is what is a good timing value for idle? it seems in gear it is always going to 18 degrees, which is the value of the High Octane Spark table, but the base spark in gear table i have set to 28 (which is stock values).

Lastly, I have noticed that when i lift off the throttle sometimes it is still reading 1-2% throttle opening. Why is this? is the IAC position affect what your TPS % shows? Do i need to go adjust the throttle blade so it goes all the way closed? or is it maybe a flaky TPS sensor? cause it isn't consistent. there is slack in the cable so it should close all the way. Wondering if some how this could be causing my issue?

Attached is a screen shot of the log where it was doing it, along with my log and tune. Any and all ideas are welcome, I have been chasing this problem for a while since i got the motor back together. Specs are a 2002 camaro with single 78mm turbo. Engine is ls1 with 4" stroker, 9.7:1 cp pistons, stage 2 BTR turbo cam.

pinstripebob
September 26th, 2019, 08:21 AM
Try doing a TPS relearn first. Unplug the TPS, turn the key on and leave it on for about ten seconds. Turn the key off, plug the TPS back in, and the next time you log it should read 0-0.4% when you're foot is off the gas. Start there and see what happens.

Sent from my Pixel 3 using Tapatalk

gpr
September 26th, 2019, 08:32 AM
is reading .4% throttle typical? seems like it reads that at the beginning of the log, then by the end it was showing almost 2%

Also what would be the correct procedure to adjust the throttle blade stop? I see it is adjustable, not sure if I should try and set it?

pinstripebob
September 26th, 2019, 08:41 AM
Sometimes they read up to 0.4%, happens to me regularly. More than that is too high. You probably aren't at your base spark in gear timing because your TPS is reading too high. A relearn should help, quick and free to try.

To adjust your blade, you want your IAC steps to be about 30-70 at idle when warm. It'll vary depending on ambient air temp and humidity. Adjust your throttle blade so your IAC steps are within that range, if needed, before doing the TPS relearn. You may need to perform RAFIG and/or RAFPN tuning as well, I believe there's a sticky covering those.

Sent from my Pixel 3 using Tapatalk

In-Tech
September 26th, 2019, 05:24 PM
Hello,
I've found if your tps voltage is above .6 you will need to drill a larger hole in the throttle body since the tps is non adjustable and will cause all kinds of idle problems. I usually strive for 15 to 30 steps at idle with big cams in neutral warm(Sometimes this might require as much as a .250" hole). With big cams that have low vacuum at idle you then need to alter the timing tables(closed throttle tables as well as off idle tables) with a much lower timing setting so the idle doesn't hang due to being "happier" at off idle since vacuum has increased during that instance. I'm not sure I am explaining it well but I fix other tuners idle issues all the time.
-Carl
p.s. don't forget the min mass air flow table vs rpm so it recovers transient.

statesman
September 27th, 2019, 01:17 AM
Another question is what is a good timing value for idle? it seems in gear it is always going to 18 degrees, which is the value of the High Octane Spark table, but the base spark in gear table i have set to 28 (which is stock values).

There's your main problem. Your spark is locking at 18 degrees and you're not getting any idle spark corrections... so it's entirely up to your idle air corrections to try to keep your idle stable, that's if your idle air corrections are even kicking in (which I can't tell from your screenshot).

I can't look at your tune file right now but maybe someone else can have a look and try to figure out why you're not transitioning to idle properly.

gpr
September 27th, 2019, 07:00 AM
Thank you for all the tips! i think I figured out what is going on, but not the cause. Attached is a screen shot, log and tune. To me it looks like when i let off the throttle for some reason once in a while the throttle is hanging (but it doesn't do it every time as you can see in the log) above the Idle tps threshold, thus when it does this it surges and isn't working and spark is stuck at 18 which is the value in high octane spark table. As soon as I stop for some reason the TPS % returns to .4% and the idle instantly smooths out.

now i'm not sure if it smooths out cause the tps is reading .4% or because it is below the vehicle speed threshold to use idle tables again....

I noticed my tps voltage is showing .7 volts when closed, I believe this needs to be .6 so I will adjust the throttle stop down. The IAC steps at idle is also over 100. I think once when i was coasting down in the log it dropped down to 70, but at idle it goes back to 120-130 usually.

So where do i go from here? I'm thinking I'm going to adjust the throttle stop down till i see .6volts as suggested. then drill a bigger hole in the blade. I also want to play with the throttle body to see if the blade is hanging up for some reason or why it isn't closing all the way once in a while. I have a spare throttle body I might also get out and try to see if it does the same thing.

Any other suggestions? Do you think the throttle blade hangs open because of vacuum from the larger engine I am now running?

statesman
September 27th, 2019, 04:47 PM
So where do i go from here? I'm thinking I'm going to adjust the throttle stop down till i see .6volts as suggested. then drill a bigger hole in the blade. I also want to play with the throttle body to see if the blade is hanging up for some reason or why it isn't closing all the way once in a while. I have a spare throttle body I might also get out and try to see if it does the same thing.

Yep, do all that. You really need tps to be 0 or 0.4 for idle... and try to get IAC counts down to about 50 at idle.

Highlander
September 29th, 2019, 01:10 PM
Your timing is also too high and your air going in the engine too low...

gpr
October 7th, 2019, 04:36 PM
Ok its been a week but I finally got some time to mess with it. I adjusted the throttle stop out and it is now reading only .5v when close. I also drilled a .25" hole in the throttle body. This seemed to make it run lean so I added 10% fuel to the VE and VE while cranking tables to help it start quicker etc.. as a quick test. Anyway I noticed that the LTFT are showing negative by a lot (probably cause I changed the ve table) but for some reason it is running lean at idle, around 15.5:1. Which i don't know why it would run that lean seemed like before it was always idling around 14.5:1, so not sure why it would pull fuel to make it run leaner.

Also the IAC steps are still around 140 even after the engine is warmed up and idling.

Attached is the log and a screen shot of the log.

Highlander, could you explain a bit more. How is the air going to the engine too low and timing too high? what should they be?

Also I noticed now the map sensor is reading about 8.3 psi now instead of 8.7 psi what it was before I drilled the larger hole.

Highlander
October 8th, 2019, 12:48 AM
Look at your timing when coasting vs the timing when you are idling... your coasting timing should be slightly lower than the idle timing and the air going through it should be higher than idle. The purpose is to create enough torque reserve so idle routines can easily bring it back to idle.

With all idle routines shut off (no iac adjustments and no timing adjustments) you want your car to naturally idle 200 rpms higher than your commanded, and then let your idle routines bring it down. The more unstable the idle is, (more reversion caused by overlap) the more torque reserve you need to achieve proper deceleration/coming back to idle and idle stability. This is contrary to what most people recommend which they want you to adjust your timing so that you get the most vacuum, thus removing ALL torque reserve from the routine and thus extremely unstable because now no timing changes make any difference in the torque output of the motor that is idling.

Highlander
October 8th, 2019, 12:51 AM
Also.. check your intake are temp sensor.. Why is it -38? this causes huge problems with VE calculations and other idle adjustments. Car needs to be 100% before touching the computer. Your trims are way too negative, which means the vehicle is overfueled and the STFTs are catching up. During those issues you will have a lot of instability. FIX THOSE FIRST.

statesman
October 8th, 2019, 01:26 AM
Also the IAC steps are still around 140 even after the engine is warmed up and idling.

Attached is the log and a screen shot of the log.

I'm on a really tight internet downloads budget right now (metered internet in Australia) so I can't download the latest version of Efilive... which means I can't look at your tune file. The screenshot of your log shows me that your idle airflow is now way too high... When you alter your airflow (cracking the blade or drilling a hole), you need to adjust the IAC Effective area table. I would recommend you shift everything in that table down about 4 or 5 cells and see how close that gets you. The really high idle airflow is what's messing up your idle trims... it's complicated, but trust me on that one. Once you get your airflow sorted out, your trims will fix themselves up and you'll probably have to adjust your VE table again.

gpr
October 8th, 2019, 03:01 AM
Also.. check your intake are temp sensor.. Why is it -38? this causes huge problems with VE calculations and other idle adjustments. Car needs to be 100% before touching the computer. Your trims are way too negative, which means the vehicle is overfueled and the STFTs are catching up. During those issues you will have a lot of instability. FIX THOSE FIRST.

At the beginning of the log I forgot to plug the IAT sensor back in, thus why it didn't want to start and idle with out me holding the throttle open. After I saw IAT at -38 I went and plugged it in and it started and idled better. (had the intake tube off to drill throttle blade)

If it is getting too much air, why doesn't it close the IAC? I thought that was the point of drilling out the hole so it would close the IAC down and be around 50 steps instead of 130? To correct the IAC effective area table, how should I correct this now since I drilled out the throttle blade?

I think the ltft are that far off from me adding 10% to the VE table in the idle rpms. I did this to see if it would idle richer, which it didn't. I will revert the VE table back to what it was.

Also I thought that it was pulling timing at idle to back off the rpms to idle at the correct RPM i'm commanding. Should I change the Idle Desired Airflow table to command less airflow at idle? Would this help close the IAC?

gpr
October 8th, 2019, 03:30 AM
Look at your timing when coasting vs the timing when you are idling... your coasting timing should be slightly lower than the idle timing and the air going through it should be higher than idle. The purpose is to create enough torque reserve so idle routines can easily bring it back to idle.

With all idle routines shut off (no iac adjustments and no timing adjustments) you want your car to naturally idle 200 rpms higher than your commanded, and then let your idle routines bring it down. The more unstable the idle is, (more reversion caused by overlap) the more torque reserve you need to achieve proper deceleration/coming back to idle and idle stability. This is contrary to what most people recommend which they want you to adjust your timing so that you get the most vacuum, thus removing ALL torque reserve from the routine and thus extremely unstable because now no timing changes make any difference in the torque output of the motor that is idling.


I'm a little confused by this. How is it even possible to get your spark timing when coasting less then when your at idle? Because when I'm going down the highway and let off timing usually goes to 40 which is what is commanded in my High octane spark table, then as I slow down and the engine rpms come down it drops back to 18 which is what is also commanded in High Octane Spark.

Or are you talking about if I am in park and rev the engine and let it come back down on its own? As the rpms come down the spark should be less then when it is trying to maintain idle? Because in the last log I posted and on the screen shot shows where I cracked the throttle. You can see the engine rev and as it comes back down it goes to the default 18 degrees and stays there for about 5 seconds before it starts changing. It looks like where the timing is at 18 degrees the rpms are too high. This leads me to believe i am commanding to much air flow or it is getting too much from the larger throttle blade hole.

Also why does it take so long before it starts to correct the idle by changing the timing? The vehicle isn't moving and the throttle % is .4% like it should be.

statesman
October 8th, 2019, 06:42 AM
How is it even possible to get your spark timing when coasting less then when your at idle?

Is this a serious question?


Because when I'm going down the highway and let off timing usually goes to 40 which is what is commanded in my High octane spark table,

Oh look, you've already answered your own question.

joecar
October 8th, 2019, 11:08 PM
Get IAT fixed as Highlander pointed out.

gpr
November 12th, 2019, 04:05 PM
Alright its been a while. Life has been crazy, so not much tuning time and its that time of the year to park the car away. However, I wanted to get the idle dialed in before I forget about it next spring.

Anyway I modified the IAC Effective Area table as mentioned by shifting the values 4 rows down. Here is a log of the tune with this modification.

It is a lot leaner at idle, but before I start messing with correcting the VE I wanted to get everything else nailed down.

The IAC steps once warm only comes down to 115. and the air flow grams/cylinder ~.3. Is this too much airflow still? I don't know what it should be on a 383ci engine with stage 2 turbo cam.

It didn't want to idle when cold unless I held the throttle open slightly. Anytime I let it close it would about die. Also it didn't idle as high as it should of when cold, even though the AFR was still pretty rich. (it was around 12:1 afr, but remember this is running E85). HOwever when warm it seemed to idle decent and didn't hunt for idle much when i would give it a little throttle.

So where do I need to go from here. Should i change the IAC effective area table a little more so the IAC steps come down? Also what would be causing it to idle lower then desired idle speeds?

gpr
November 12th, 2019, 04:06 PM
Also I noticed in the log that when I open the throttle the IAC also opens, is this normal?

statesman
November 12th, 2019, 11:46 PM
So where do I need to go from here. Should i change the IAC effective area table a little more so the IAC steps come down?

You shouldn't be adjusting your IAC effective area table for the purpose of reducing your IAC counts (but that does happen). You adjust the IAC effective area so that you get your desired airflow and actual airflow match. If your airflows don't match, then you need to adjust that table until they do.



Also what would be causing it to idle lower then desired idle speeds?

Most likely not enough commanded airflow.

statesman
November 12th, 2019, 11:47 PM
Also I noticed in the log that when I open the throttle the IAC also opens, is this normal?

Yes.

pinstripebob
November 13th, 2019, 12:03 AM
Take note of what Statesman pointed out, he knows what he's doing.

There are a few things I learned that should help you out here. Like Statesman alluded to, your airflow may not be correct. You can correct it by performing the RAFIG process. If you have an auto trans, do RAFPN as well. You can read about how to do that here: https://forum.efilive.com/showthread.php?26435-RAFIG-PDF-Includes-all-of-SSpdmon-idle-info

Also as pointed out, your desired airflow and actual airflow need to line up, which is why you would modify or shift your IAC effective area table. What I found helped dial in that table was logging IACDES_B and DYNAIR. I setup a custom PID that was equal to IACDES_B minus DYNAIR. You want the difference between these two logged pids to be zero when your engine is at operating temperature, above 80C. Below that they may not line up, but focus on when your engine is at operating temperature first. If IACDES_B - DYNAIR is positive, shift B4403 up. This means shift the table so if 1 IAC step was 18.0 sq. mm, now 1 IAC step is 20.0 sq. mm. Again, do this at operating temperature. Once you get this done, perform RAFIG (and RAFPN if you have an auto trans) and your airflow should be spot on.

Once B4403 and then B4307 are corrected, look at your IAC steps. Shoot for 30-70 (or less according to some people, I'm an amateur to so take this with a grain of salt) IAC steps when you're idling at operating temp. This will vary based on humidity and air temp. If you're in that ball park, you're good, but make sure your TPS is reading 0 or 0.4%, no more. Do a TPS relearn if needed, or close your throttle blade a bit. This was discussed earlier in this thread.

Get airflow set, check your TPS and IAC and make any adjustments as needed, then repeat the above process. Tuning is iterative, so expect to run through things at least a couple times until they are dialed in.

gpr
November 13th, 2019, 04:12 PM
Why do you want the IAC steps so low? What is wrong with having the IAC open more?

Also how do you know if it is getting too much air or not enough at idle? Is everyone basing that off of the spark timing? Thus its getting too much air and trying to idle high, so it retards the spark past what your base spark of (in my case 18). Therefore you know its getting too much air?

I did the RAFPN process tonight, however something seems wrong. The RAFPN was at a constant 2.0 the entire time. Is this like a maximum number? or did I do something wrong?

Attached is my log file of the RAFPN test.

The odd thing I noticed tonight is it started up and idled just fine. I didn't have to hold open the throttle when cold, but the IAC steps were also higher. I wonder what the difference is? The car hasn't moved and the tune hasn't changed....

gpr
November 13th, 2019, 04:14 PM
Here is a screen shot towards the end. You can see RAFPN never changes the entire time....

In-Tech
November 13th, 2019, 04:30 PM
You want the IAC steps fairly low so you can use the entire IAC function, The IAC is just an electronic vacuum leak, so you use your blade opening to do the majority of the idle function(keep your tps in range .5-.6v with big cams you usually have to drill a bigger hole in the throttle body to keep tps voltage in range or modify the bolt holes in the tps) then let the computer handle the rest. When you have the IAC near full open(around 150 steps usually) you are out of control.

gpr
November 14th, 2019, 11:45 AM
You want the IAC steps fairly low so you can use the entire IAC function, The IAC is just an electronic vacuum leak, so you use your blade opening to do the majority of the idle function(keep your tps in range .5-.6v with big cams you usually have to drill a bigger hole in the throttle body to keep tps voltage in range or modify the bolt holes in the tps) then let the computer handle the rest. When you have the IAC near full open(around 150 steps usually) you are out of control.

Isn't the max IAC steps around 300? As the last log I provided when the key was turned on and engine cranking IAC hit about 280 steps. I would think you would want your IAC in the middle at around 150 steps. Then it can go in either direction to open or close to control the idle speed?

Anyway, anybody have any ideas on why the RAFPN values are constant during the entire log?

Doc
November 15th, 2019, 02:40 PM
Isn't the max IAC steps around 300? As the last log I provided when the key was turned on and engine cranking IAC hit about 280 steps. I would think you would want your IAC in the middle at around 150 steps. Then it can go in either direction to open or close to control the idle speed?

Yes, ~300 steps. You are at the side of your house with a garden hose. You turn the valve open a 1/4 turn. You have flow out the spigot. Turn the valve another 1/4 turn to 1/2 open on the valve. You have more flow. Turn the valve another 1/4 turn to 3/4 open. You have more flow. Make that last 1/4 turn to the valve wide open....do you have any appreciable more flow? Nope. I have found at 16' above sea level, NE FL, one has about 170 use-able steps. In order to reduce the demand on the lAC opening (increasing) the throttle stop set screw to give the necessary bypass airflow. Adjustments to idle set screw should only be performed with the vehicle fully warmed up. Throttle Body set screw / TPS relearn must be performed as well.

statesman
November 15th, 2019, 03:13 PM
Back in September, you said this....


I'm thinking I'm going to adjust the throttle stop down till i see .6volts as suggested. then drill a bigger hole in the blade.

Have you done this yet?

gpr
November 16th, 2019, 02:50 AM
Back in September, you said this....



Have you done this yet?

yes, drilled a .25" hole and adjusted throttle stop down to .5v when close. Also did a tps relearn.

I tried the RAFPN process to try and adjust the air flow at idle but for some reason it didn't work and showed a constant the entire time.

I adjusted the IAC step table down a few rows like suggested but IAC steps are still around 140ish.

Doc
November 16th, 2019, 04:04 AM
Sorry, forgot to ask, stock TB? The key part of your last comment, "adjusted throttle stop down to .5v" This does not make sense to me. When you move the screw the voltage IS going to change. TPS reset, or relearn or whatever, IS the process where the pcm gets it's NEW electro-mechanical "ZERO."

Try this, physically remove the TPS sensor from the TB. With KOEO, observe the TPS voltage while cycling the TPS with your finger 0-100% Your TPS should have a spring inside that helps pull back the wiper to zero position. An old or worn out spring or the plastic not fitting snug enough on the shaft of the TB will produce the phenom of an inconsistent zero. If zero position displays ~+/- .6v don't worry about it.

Bear in mind, the first time pwr/grnd & KOEO the pcm will "record/remember" the physical/mechanical position of the TB shaft as it will produce the voltage output of the TPS sensor displayed on your scan tool.

Sometimes the TPS reset procedure can be a PITA. That is forcing a failure of the TPS.

Big picture, increasing the position of the set screw will (or drilling the TB, not my favorite in 2019) will provide more bypass air to achieve your target idle. The pcm will not "need," the IAC counts. The IAC counts will go down on their own.

2019
Holley LS Throttle Bodies 112-581
A little late to the party but, Holley had some really great ideas with these TBs. Notice the adj bypass air screw on the pass side? You can turn that sucker as much as you want, no TPS reset. On the driver's side, the TPS position is adjustable, so you can get your electrical zero nailed down as well. The adj TPS is really handy on big cam / heads. These TBs are not cheap but, they make things a lot more fun. There are two styles. I would recommend the tapered lip for a street car. The hogged out to the max non lip, I would use on a track only car where you want / need max airflow and don't care about street manners.

MSURacing
November 16th, 2019, 06:25 AM
Ok, just going to ask the question. After you flash the cal in and wait for the countdown, are you keying on, key off, and then starting it?

statesman
November 17th, 2019, 12:48 AM
yes, drilled a .25" hole and adjusted throttle stop down to .5v when close. Also did a tps relearn.

I tried the RAFPN process to try and adjust the air flow at idle but for some reason it didn't work and showed a constant the entire time.

I adjusted the IAC step table down a few rows like suggested but IAC steps are still around 140ish.

Okay, i think your engine is getting a lot of air. I just looked at your last screenshot and your spark is really low... it shows an average of 12.1 where it should be averaging 20-24. Are you commanding low spark or is it just doing this by itself?

gpr
November 18th, 2019, 06:43 AM
Awhile back i had adjusted the throttle stop open to get more air at idle. As a result the TPS was showing about .7 or .8 volts. Thus i adjusted it back to where it is reading .5 to 6 volts. To increase the air flow i drilled the throttle body plate. This is on a stock throttle body. Then once the screw was adjusted to where it was reading voltage i did a tps relearn to get the % opening reading correctly again.

gpr
November 18th, 2019, 07:07 AM
Okay, i think your engine is getting a lot of air. I just looked at your last screenshot and your spark is really low... it shows an average of 12.1 where it should be averaging 20-24. Are you commanding low spark or is it just doing this by itself?

I'm commanding 18 degrees. I tired the RAFPN method but it didn't work and showed a constant the entire time.

Here is my issue. I know i need to adjust the airflow at idle to lower it. However there is a couple ways i can do that.
1. Should I keep playing with the B4403 IAC Effective area table to increase the amount of air flow it is getting per step? This seems to me like a bad idea because the amount of air flow per step should be the same no matter what size hole is in the throttle body blade. (I'm not changing the IAC in anyway so it won't flow more per step)

2. Simply reduce the Desired Airflow at idle because the bigger hole is letting more air in, thus i don't need to require the PCM to allow as much in. By doing this I assume it will close down the IAC steps. Then simply dial in the VE table to get the correct AFR.

Am i on the right track or is there a better method I should be trying?

statesman
November 18th, 2019, 09:11 PM
Both of those options are wrong.

Increase your idle spark.... set it to around 26.

Increase your desired airflow.... and yes, I do mean INCREASE it. Add about 2grams to every value in your table.

You'll notice that I gave you a metric value to increase airflow... change your tune file over to metric and tune in metric. Also log in metric. I know it can be hard to adjust to, but it will make life easier for you in the long run.... and it will make life easier for those of us trying to help you.

When you've made those changes, do another log and see what values you get for your RAFPN.

gpr
November 19th, 2019, 10:08 AM
Both of those options are wrong.

Increase your idle spark.... set it to around 26.

Increase your desired airflow.... and yes, I do mean INCREASE it. Add about 2grams to every value in your table.

You'll notice that I gave you a metric value to increase airflow... change your tune file over to metric and tune in metric. Also log in metric. I know it can be hard to adjust to, but it will make life easier for you in the long run.... and it will make life easier for those of us trying to help you.

When you've made those changes, do another log and see what values you get for your RAFPN.

Please explain the reasoning behind this? It is already pulling timing to control the idle, why would more air and more spark help anything????

statesman
November 19th, 2019, 01:41 PM
Your idle spark should be around 26... and I wanted to see if it takes all the extra air you give it. If you don't want to give it any extra air, then just set timing to 26 and do a log.

gpr
November 21st, 2019, 06:55 AM
Here is a screen shot of the log. Also note that IAC Effective area was put back to stock as it had no affect on IAC steps at idle.

The first screen shot I reduced Desired Airflow by 10% (~1 g/s) and performed RAFPN log again. As you can see it is still pulling timing and idle is lean. However it is idling at the desired RPM, but the IAC steps are still high.

The second screen shot I did as suggested and added 2g/s airflow to the entire Desired Airflow table, and set the base timing to 26 degrees. As you can see it idles way too high with all that air and is pulling back timing, IAC steps are still the same. I believe it is idling so high because it can't reduce the timing any further since it was set at 26 degrees.

(note in all my screen shots the RAFPN is displayed in both lbs/min and g/s for the metric folks)

Everyone suggest IAC steps of 50-70, how do you achieve this? every change made has no affect on IAC steps.

pinstripebob
November 21st, 2019, 08:04 AM
Have you checked for vacuum leaks? Unmetered air could be a cause.

Sent from my Pixel 3 using Tapatalk

statesman
November 21st, 2019, 09:38 PM
The second screen shot I did as suggested and added 2g/s airflow to the entire Desired Airflow table, and set the base timing to 26 degrees. As you can see it idles way too high with all that air and is pulling back timing, IAC steps are still the same. I believe it is idling so high because it can't reduce the timing any further since it was set at 26 degrees.

That's what I wanted to see.... it took all that extra air. In your first screenshot your RAFPN is showing 1.88g and in your second screenshot it is showing 0.00g. Something is wrong with your airflow corrections.

Post your current tune file. I'll update to the latest software this weekend and then I'll be able to look over your tune file.

gpr
November 22nd, 2019, 05:44 AM
The tune named "- 2002_Camaro_COS_383_0035 test" is the one where i added 2g/s of and set the base idle to 26 degrees.

the tune named "- 2002_Camaro_COS_383_0034" is the tune before those changes were made.

statesman
November 23rd, 2019, 07:01 PM
Try this tune file. Do a RAFPN and post the log.

joecar
December 9th, 2019, 12:43 AM
Subscribing...

gpr
June 5th, 2020, 10:29 AM
Well I finally got the car back out and took it for a spin today. This tune file does seem to have helped with the surging when coasting to a stop. However, now it wants to die when coming to a stop. I have to hold open the throttle slightly when coming to a stop to prevent the engine from stalling. Thus I'm assuming I need to command more idle air flow.

attached is a log file.

statesman
June 5th, 2020, 03:42 PM
Did you do a RAFPN before you made this log or is the log made from the exact file I gave you?

gpr
June 7th, 2020, 09:45 AM
that is the exact file I received. I have performed a RAFPN and RAFIG. For the in gear one I simply put it in drive and held the brake, odd thing is it shows needing less air then in park/neutral? is this normal? or should I take the P/N one and add slightly to get the values for in gear?

statesman
June 7th, 2020, 09:52 AM
Does the engine still want to die after doing the RAFIG?

gpr
June 9th, 2020, 01:09 PM
Yep, pretty much if it is in gear and you are going slow, if you let off the throttle it will die. Or almost anytime you come coasting to a stop, it will die once you stop. I'd guess as soon as it enters "idle" mode is when the engine will dies. attached is a log and the tune file with the desired airflow after doing RAFIG and RAFPN.

statesman
June 10th, 2020, 02:08 AM
Okay, something is going wrong with your RAFIG... your "In Gear" values end up a lot lower than your "Park/Neutral" values.

Try this update. Do a RAFIG but don't apply it to the tune, just log it... then do a short driving log and post both logs.