Idle Problem and more

[swingtan]

OK, a few other things that may help.

1. You are running around 25gm/S of idle air flow. This is massive and leads me to think that you have either drilled a hole in the TB blade or it's a result of the idle airflow correction tables being zeroed out. The average commanded spark advance is only 9.9' while the commanded in the tune is 13'. This also indicates the engine is getting way too much air at idle. The commanded idle air is only about 7gm/S, which is a bit low IMO, so I'm assumiong there is a 6mm hole in the TB blade.
   
   Unless you have a lumpy cam in there, I wouldn't have a hole in the TB blade. I am assuming you have a couple of turbos, though these should not alter the required idle air by much.
   
2. The Idle spark correction is not going to help until the engine speed has gone too far off. Then it's going to add way too much timing in a single hit and probably cause over correction swings. Going from 0' correction to -12'/+15' correction in the space of 16RPM change is not going to help anything. Even at your quite stable idle settings, the spark is going from 0' to 14' in the space of one frame. Much too much change IMO
   
3. Idle Integral steps. I know that Hymey has run with these zeroed out, but I think that was on a very large cam, NA setup. I've never done this as I found it caused the idle to hang on deceleration and hunt badly unless everything else was absolutely perfect. I'd put some values back in there.
   
4. The lean idle is interesting, especially for a fast restart. Can you keep the restart going to a point it idles OK? I'm wondering how long the lean condition lasts for. Actually, I just looked at your VVE. It's pretty bad, that's putting it very nicely..... The VVE shows that the engine will be running really rich just before the stall, at a guess, going from the information at hand, I'd say you were getting about a 4:1 AFR as it stalls. No wonder it smells like fuel.
   

So basically, I think there is no one magic bullet here. I'd start with making the VVE a bit more sane, then move on to base idle air and then corrections. I'd probably guestimate the VVE for starters, pulling 10% of the 400 RPM to 1000 RPM cells over 55kPA MAP. Then use stock values in the base idle air, Integral steps and Idle spark correction. Then fine tune from there making small adjustments.

Simon

[etmotorsports]

There is a large cam in this car, as far as i know there is no hole in the throttle body, i zeroed out the corrections a while back to dial in the a/f at idle. Here is the odd part about this, the car ran and drove for about 2 months until the tranny broke, not put a new one in and it is doing this stuff. Granted it didn't drive great much better that it was on the maf tune when i got it. It would die now and then coming to a stop but no every time. Before i had a chance to work it out the tran blew. I agree with what you are saying the ve needs work and spark correction i noticed is not correct imo either. I actually leaned out the ve table where it was dieing and it didn't seem to help but i am gonna try that some and maybe it will lead somewhere. i am gonna smoke test it to for an intake leak i am wondering about that but i haven't touched any of that while doing the trans. Thanks for the opinion swing always helpful

[etmotorsports]

Swing where are you seeing the 25 g/s of idle air flow?

[swingtan]

I have a calc PID to get air flow "gm/S" from RPM and SD-gm/Cyl. It's showing that at idle, you are moving 25gm/S of air flow. This of course assumes that idle fueling is correct ( which I think it's a bit off, but not a huge amount ). I also used the IBPW to rational the fueling before the stall. At 1000 RPM, you had an IBPW of about 2.8 mS, then as the stall occurs and the RPM drops to say 200, the IBPW is still close to 2.8 mS. So I'm thinking it's flooding as the stall occurs and the ECM can't correct for that condition.

Simon

[etmotorsports]

OK i checked no holes in throttle body or vaccum leaks all is good there. I have changed the ve and other thing and i am sure that is the correct numbers when it is at idle. When i changed the ve to some more reasonable numbers at 73 kpa and 800-1500 rpms it seems to help a bit it will still die. Here is the million dollar question after a flash it starts up fine after shutting it off and starting again right away it acts this way i cannot find any tables that would make it fuel off of something else, i am at a loss i will post up the latest tune and log later

[swingtan]

Post the latest tun and log, I'll have a look.

[etmotorsports]

sorry had other things to fix some other broken cars, since this is one has a bad attitude it is on the back burner

Ok here are the latest logs and file from yesterday.

Camaro_dies_0010_0004.efi

2010_camaroSS_Engine_las.tun

[swingtan]

OK, try this for starters. Please note that I simply had to mess with the VVE, it was really, really bad and I'm sure would have caused massive issues if it was taken out to the red line of a "big" camshaft. Of course, the changes I've made are pretty blind and could be just as bad. Run it up on the dyno with a WB in place and check the fueling. I don't think it could be any worse than the previous one though....

I've played with idle control, min idle air and cranking tables. All should help with the idle, but I think the kicker for this one is {B1847} and {B1848} which are new calibration tables with the latest update. They seems to control the idle speeds, just after starting and before the "default" idle speed settings are used. Hopefully I'm reading it correctly and the idle control should be better.

2010_camaroSS_Engine_swingy_0000.tun

Simon.

[etmotorsports]

Thank you swing, it looks way to lean to idle but i will gladly give it a try, and see. I am at such a loss on this car it is not even funny. The fact that you think it has way too much fuel at idle i am wondering if the injector calibration is right for what is in the car. I never checked that when i tuned it on the vve map. I was told there were 60lbs injector but i don't remember if i every actually ran the part number to see what they were.

If your tune still acts the same way i am thinking it is the ecm but i need to confirm that 1st before i spend the money thanks again i will let you know what happens

[etmotorsports]

0280158117 This is the part number of the injectors in the car shows to be a 52 lb/hr bosch injector. here is the table for the injector flow rate i am not familiar with the e38 i am not sure if this is right.

see next post messed up the copy paste