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5557nut
May 28th, 2021, 02:41 AM
I have search EfiLive, read Swingtans sticky's and used his settings, read RingRam's tuning doc, and every tutorial I could find for mafless tuning. I am still missing the ohhhhhh yeaaa! factor. I've been struggling with how the idle, air, and fuel tables interact. So there, I've got enough knowledge to be very careful.
My ride is a 55 Chevy with manual 6spd, LS3, Texas Speed cam(229/236 629/615 lift, hi-ram intake, stock injectors, 2" headers, and 3" exhaust.
I try to start 5 to 6 times also feathering the throttle to finally start. It starts to start then dies. It helps if I try very little throttle.

I know I will get some crap because of the many changes Ive made to each flash. Ive only done 8 flashes so I'm read to (an know I should) makes small changes. But one would have to know what they are looking at to make those changes. I just don't get what params to change based on the scan readings. Side note...when viewing a log I use to be able see the changes by moving a mouse across the dashboard graph but the vertical line does not display anymore?

Hopefully someone can decipher what I've. Once started the engine runs great except when I stop at a light then the idle stays high for a long time and sometimes will not come down at all.. I do have 2 wideband o2's installed but not connected to the V2 (can't figure it out). At idle they both read 11.7, driving they are around 14.5. but hard to monitor while driving.
I included a cold start log, the tune I flashed, a log after the cold start n flash, and an excel file showing the 8 tunes flashed and the setting changes.

Thanks

joecar
June 1st, 2021, 09:32 AM
( idle tuning is an art )

Post your stock tune also.

Try reading this (you will have to translate some stuff to E38): Idle-Tuning-Helpful-Info-Inside (https://forum.efilive.com/showthread.php?4661-Idle-Tuning-Helpful-Info-Inside)

Basically: you have to make airmass/airflow match actual. And make spark advance match on transitions between tables.

5557nut
June 1st, 2021, 09:36 AM
Thanks...I had not found that thread...I'll read it, then ask questions

5557nut
June 1st, 2021, 10:53 AM
Being new I have a problem interpolating written description to param/table numbers. I don't think I am verse enough to translate the link you referenced to my 2010 E38 ecm. The idle airflow corrections really thru me. The excel file I posted shows my adjustments with the first column showing the original settings.

Since I have changed to a mafless tune using swingtan and others tutorials, I've gotten lost. I think I must revert tpo the original tune, change to all the mafless settings and start from there. I am not understanding a lot since most of the tutorials were written pre-2010 and don't always reference the settings from preV7/V7 vs V7.5
Example I finally figure out that B0101 is now B8101 but others are not as direct.

I could use a good EfiLive tutorial that describes/defines g/s relating to fuel, air,and spark. There has got to be 10-12 tables that interact. I think it's more knowing what I'm looking at and what it means.

Thanks joecar...still confused

5557nut
June 3rd, 2021, 01:42 AM
I really could use some help on this cold start issue and hi idle.
I am posting my tune and recent log with WB O2's recording afr, lamba, and eq.
The log is not driving just sitting in shop. runs great when driving but I know could use fine tune.
Thanks