Oscillating Idle

[turbo conversion]

I see in the log idle is better but still going a little lean.

Try setting the VE cells up to 50 kpa to 115 so when map rises it will not go lean.

I think turning off idle advance and adding a little fuel at idle will help a lot.

David

[Blown88GT]

...
1. I see in the log idle is better but still going a little lean.
2. Try setting the VE cells up to 50 kpa to 115 so when map rises it will not go lean.
3. I think turning off idle advance and adding a little fuel at idle will help a lot.

David

1. Yes. Might be due to air pump (supercharger). BOV not large enough to blow off 100% at idle. MAF goes from 3-9 gm/sec.
2. 50 is far above idle, which is 20-30.
3. Will try changing Idle Advance from Adaptive to RPMs. Fuel was added previously.

[ashford]

just for curiosity sakes can you back out the idle screw and see if you can reach 80-90%dc

[turbo conversion]

The kpa at idle is not 20-30 in the data log, it swings from 32.9 to 45.5 that is why I said 50.

As kpa approaches 40 fuel is being trimmed and at 45 even more fuel is being trimmed.

Try turning off all idle advance settings so the timing at idle will be a consistent 16 deg.

David

[Blown88GT]

just for curiosity sakes can you back out the idle screw and see if you can reach 80-90%dc

I don't know what "80-90%dc" means. Besides, backing out the screw will have no effect since the IAC (IAB) will compensate.

The kpa at idle is not 20-30 in the data log, it swings from 32.9 to 45.5 that is why I said 50.

As kpa approaches 40 fuel is being trimmed and at 45 even more fuel is being trimmed.

Try turning off all idle advance settings so the timing at idle will be a consistent 16 deg.

David

I was just watching the live "tracer" move around the cells in real-time.
Last log (2016-01-21_IA_RPM.msl) shows 12.0 to 12.2, even though table is requesting 16.
I think it would be better to change Apply As: from "adder" to "set value"
Set Value = timing is set to the value from the curve
Adder = value from curve adds to existing timing.

Will try tomorrow, weather permitting.

[lagos]

You have 100% gain in your EGO correction PID settings. That will oscillate like crazy.
Turn off EGO correction to verify that its causing the problem.
Then turn it back on and try something like.

P=30
I=40
D=30

Also your VE table is not tuned at all. Use autotune to map out a table for you.

[Blown88GT]

...Also your VE table is not tuned at all. Use autotune to map out a table for you.

Looks like he's using maf with ve table to trim it.

You must have missed this.
Looks like he's using maf with ve table to trim it.