After-Throttle low Idle issue
#41
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Thanks. I wanted you to set to 5 g/s adaptive idle max to see if it would keep trying to trim higher, and it did. Toward the end of the log, you had 5 g/sec long term AND short term airflow. I would go ahead and drop those to 2.00, which is where I keep mine.
Notice, prior to 22 minutes into the log, your idle was very stable, and spark kind of moved around from 12-20 degrees? Then after that throttle blip around the 22-23 minute mark, it went to straight 18 degrees and that's when idle got unstable? That's one thing we need to fix. Then, at the 25 minute mark, you kill it and restart, and adaptive spark returns, until you blip the throttle again at 26:30.
The other is that you are 16-17:1 on your WB. Are you deliberately running that lean? If not, i'm assuming you know how to correct that. At 26:30 after that throttle blip you're at 18:1. I understand idling lean, but you need some fuel in there. I'm pretty sure that this is the reason it is commanding so much idle trim airflow.
One other observation -- when you are key on engine off, you're only seeing 81 KPa, which I typically expect to see around 100. This has me wondering which map sensor you have. you're on the 3-bar OS, which typically means your running boost...
Notice, prior to 22 minutes into the log, your idle was very stable, and spark kind of moved around from 12-20 degrees? Then after that throttle blip around the 22-23 minute mark, it went to straight 18 degrees and that's when idle got unstable? That's one thing we need to fix. Then, at the 25 minute mark, you kill it and restart, and adaptive spark returns, until you blip the throttle again at 26:30.
The other is that you are 16-17:1 on your WB. Are you deliberately running that lean? If not, i'm assuming you know how to correct that. At 26:30 after that throttle blip you're at 18:1. I understand idling lean, but you need some fuel in there. I'm pretty sure that this is the reason it is commanding so much idle trim airflow.
One other observation -- when you are key on engine off, you're only seeing 81 KPa, which I typically expect to see around 100. This has me wondering which map sensor you have. you're on the 3-bar OS, which typically means your running boost...
#42
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I will change the adaptive idle values down to 2.00g/s .the idle when first starting the car is awesome, but once I give the car throttle it doesn't return to adaptive idle values. I did try turning the car off to restart to see if it would return to idle values,and it does. weird. do u belive this is do to running lean? I also noticed my iac values are high when this happens . I,m running lean I know,that I know how to fix 'main ve table' toward the end of the scan it does get really lean 18afr due to hot iat temps always had that issue. my map sensor is a 3 bar ls9 sensor, im not boosted yet want to see what this setup will do before adding a single turbo again u are the man car is responding very nicely to your changes can not thank u enough.
#43
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Glad to help. I do not think the lean AFR is the reason for the failure to return to adaptive spark, but I am positive it is the reason the car is opening the iac so much. Rpm is low, it compensates by adding air. That is just how the controller works.
I will try to dig around some and see if I can come up with a good reason why it will not drop into adaprive spark on return to idle.
I will try to dig around some and see if I can come up with a good reason why it will not drop into adaprive spark on return to idle.
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do u think zeroing out stall saver mite help. maybe it is messing with idle? its wicked cold and snowing here today or I would have tried to dial in the afr supposed to be 55-60 degrees by the end of the week.
#45
Im guessing that, Throttle Follower Decay (p/n) needs to have a number for all speeds, no zeros or the airflow will just hang.
Edit: Might not actually matter as its M6 trans.
Edit: Might not actually matter as its M6 trans.
#46
Also I see its set as automatic trans still in trans section. I don't know much about that stuff but that might effect things. Usually manual trans stuff doesn't use p/n tables.
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I think idle hang is due to it running lean. trying to figure out why its not returning to adaptive spark during idle. not sure if maybe because its running lean and higher than normal rpm due to running lean its not returning to idle adaptive spark
#48
I'm guessing its not returning to adaptive because of the Throttle Follower Decay (p/n) table having 0 in it. It wont go to adaptive until follower airflow is gone. Follower air cant go down if it decays at a rate of 0. Since it still thinks its using an auto trans its using p/n tables. Id at least try that.
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so change the trans setting to manual? to see if that help? throttle follower decay does have values in them just not until 6mph witch the ecm has no idea on what my mph is. ecm thinks im in park all the time
#50
I would start with just the Throttle Follower Decay (p/n) table and see if that works. Changing to manual at this point might change alot more things all at once.
A 2000 camaro auto has this for 0/2/4/6/8/10/14/18+mph This is in G/S.
0.0049 0.0078 0.0098 0.0400 0.0996 0.2998 0.7998 1.0000
A 2000 camaro auto has this for 0/2/4/6/8/10/14/18+mph This is in G/S.
0.0049 0.0078 0.0098 0.0400 0.0996 0.2998 0.7998 1.0000
#51
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Originally Posted by David_viny
I would start with just the Throttle Follower Decay (p/n) table and see if that works. Changing to manual at this point might change alot more things all at once.
A 2000 camaro auto has this for 0/2/4/6/8/10/14/18+mph This is in G/S.
0.0049 0.0078 0.0098 0.0400 0.0996 0.2998 0.7998 1.0000
A 2000 camaro auto has this for 0/2/4/6/8/10/14/18+mph This is in G/S.
0.0049 0.0078 0.0098 0.0400 0.0996 0.2998 0.7998 1.0000
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darth v8r and david viny I cant thank u guys enough. my car is idling awesome, I posted latest tune and scan. the scan is kind long sorry but I couldn't get enough of listing to my car idle now. lol it surges just a little after I rev it but I aint complaining. beyond happy with the advice I got from both of u guys.
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got to take car for a small test drive today. its running lean and will fall on it face when trying to go full throttle I think maybe fuel pump is going bad or possibly a clogged fuel filter. here is the scan from the drive if u guys see any tune issues please feel free to discuss
#55
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got to take car for a small test drive today. its running lean and will fall on it face when trying to go full throttle I think maybe fuel pump is going bad or possibly a clogged fuel filter. here is the scan from the drive if u guys see any tune issues please feel free to discuss
Does it fall flat only when commanding WOT, or anytime you stab the throttle? I haven't looked at your attachments as I am currently at work.
If it's not in the tuning, it could definitely be one of your guesses. When this happened to me (as in, I was barely able to accelerate much at all, it would fall flat and misfire when giving any throttle too quickly) it was caused by my main feed hose inside the fuel housing in the gas tank coming loose, and providing just enough fuel to cruise at around 2000 or so rpms.
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yes seams like possibly a fuel issue to me. try to get into the throttle and it completely falls on its face. getting more shity weather here so not able to bring it to work to take a look at things