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When tuning idle recovery, only add timing under the target. Do not retard when above target, yet. This only tests the "cushion" of advance to limit the rpm if it drops under target. Ignore rpm over target for now, and when your decel idle recovery is good, then add a little timing retard only as needed to limit over-target bouncing. The point of this is to (initially) avoid any action (retard) that tries to pull or accelerate rpm down when it is above target rpm, aggravating the recovery issue. I hope that makes sense. :roll:

Your timing from your tune, modded for recovery. This is the equivalent effect of Idle Advance on 900 warm idle in the Spark Table that you are looking to test. Hard positive timing application only if falling under-target. Play with amount and speed (rpm -50, -100, etc) to find a happy spot:
MattSkelton_equiv_SpkTbl.jpg (60 KiB) Viewed 199 times
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By MattSkelton
Got a few more logs here and the current tune.

PSIG thanks for your reply.

I am using the added method of Idle advance the logs and current tune were used with this IA curve
Screenshot 2022-11-24 172153.jpg
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But if i am understanding you i need this, albeit you have set it on the Timing map so i have added the Idle advance to the spark table to give the totals you suggest , or have i stuffed this up?
Screenshot 2022-11-24 172709.jpg
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I would be cautious using both the timing trough and the idle advance. They may fight each other.
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By MattSkelton
LPG2CV wrote:
Thu Nov 24, 2022 8:04 pm
I would be cautious using both the timing trough and the idle advance. They may fight each other.
Do you not use the Idle control feature then and just mark it off as opposed to added or switched?
I'm just saying to be cautious. Perhaps just use the trough in the first instance, as it is easier to observe the result of it in the spark table .
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Are you reviewing your logs in MegaLogViewer? I posted the modded timing table as an example of what you are trying to begin tuning decel idle recovery with. As I said earlier; while you can do this with Idle Advance, it may be simpler and more familiar to do it with the timing table. When good results are found, transfer that function to Idle Advance.

Yes, you want a lot of timing advance quickly, only when rpm is under target, as the section of modded Spark Table illustrates. Notice it adds 15° additional timing within -100 rpm of idle. Notice it does not retard, ever, when above target idle (this may change later). Whatever you were doing in your last log, the ignition shows hard retard when under 2000 rpm. :x This pulls the rpm down faster, making recovery more difficult.

I don't know how to make the concepts simpler, and maybe others can jump in here. Perhaps turn Idle Advance OFF and use just the Spark Table for testing. As it is now, it is trying to pull engine rpm to 900 anytime it is between 901 and 2000 rpm and under 5% TPS. If you insist on beginning with Idle Advance, at least reduce Active below rpm to perhaps 1200 max, and TPS under 1 or 2%. No retard. It's fighting you, not helping you.
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By MattSkelton
PSIG you have spent the time looking at my logs (I have HD Log viewer but not entirely sure what i am looking at is there a good guide somewhere for beginners?) I am going to TURN OFF Idle advance settings and set up the spark table as your post above.
Your knowledge is better than mine and I am sure you have a better handle on this than me!
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