Idle AFR Mystery, and AE tuning.

[MustangMike]

Tuning my friends car and i'm seeing some odd issues.
When at temp (180-205 deg) I can tune the idle area to be stable at 14.0 AFR or so and it idles great and then write/save the tune. If we then take off and drive for a while or even turn the car off and back on a few minutes later (still above 180 temp) it will go pig rich at 11.8-12 and idle terrible. Seems like I chase it back and forth.

Another issue I'm chasing is the AE. We were having a bucking / lean issue if we didnt feather the clutch so I richened the VE area it was happening in to get as close as possible before touching the AE.
The problem is much better ( i.e. drivable) but far from ideal still. You can see in the log a bunch of throttle stabs in a row.

I know the VE table is whacky outside the cruising area we have been tuning in but the car is a beast above 3500 rpm, I will need to scale the rest of the table and some dyno or track time.
Can someone take a look at the attached log and see what AE settings it wants?
Is there a setting that adds or removes fuel over a certain temp? Sometimes tuning while idling we can get up to 200+ deg.
Anything else you see to improve the tune I'd like to know, always learning.
Really appreciate all your help!

Info: MS3/MS3x, 408 Ford windsor, mild cam, single plane intake, fuel rails, 60lb injectors, twin turbo
I didn't notice any TPS noise.
Accurate (according to Ford), Injector dead time settings
Fuel pressure steady at 39-40 psi

[Matt Cramer]

This has a pretty common issue on 5.0s - MAT heat soak. If the engine is shut down, the MAT sensor absorbs heat from the manifold and gives a false high reading. You can try dialing this out with MAT / CLT Correction, or relocate the sensor upstream of the throttle body.

[MustangMike]

That's a good point, if MAT went above 200 it would pull timing and drop the idle lower into cells that are richer.
I could lean the cells under the idle to force it back up or set them same as idle.

I just checked the car and the MAT is on the back of the throttle body (carb) bonnet, so its in the airstream and not soaking on the manifold.
Checked the logs and see MAT temps of only 101-113 when the CLT was 178-188 so looks like the intercooler is working good even in the 90 deg miami heat.
I will have to get a log when I see it happening.

How does the AE look compared to the logs?
My novice view is added fuel % was too high. I see the log where a throttle stab would cause the afr to go rich 1 point so i took out 2%.

[Blown88GT]

Your Ignition Table at low load & low rpm has too much advance.
Maybe because Idle Advance is turned off?

[MustangMike]

The cells in the 600rpm low load column that are high (30) are to bump up the idle if it tries to stall. If this is bad practice I can change it. We haven't tried to used closed loop idling yet as it starts and idles fine, and has no AC or anything.
24 deg idle timing maybe a little high. I can try to lower it, but its a lumpy cam, bored and stroked with a single plane intake, sucking air through alot of plumbing at idle.
Sometimes it turns over slow which is odd because it has a high torque starter low compression, and MS3 cranks at 10 deg, right? Ill try to see if cranks slow because of heat or something.

[Blown88GT]

The cells in the 600rpm low load column that are high (30) are to bump up the idle if it tries to stall. If this is bad practice I can change it....

I know why you did it, but you're just guessing at the value & cells to set. Your idle probably jumps between the 1st & 2nd columns.
You said you have an "Idle Mystery"; you're best guess could be making it worse.
Manual settings only required when automatic ones don't work. I would change it.
Try:
Idle Advance On = rpm
Apply as = Adder

You can configure one of the gauges to display Ignition Advance & watch it in real time.

BTW: I've tried MAT in both locations, no noticeable difference. The thermistor is at the tip of the sensor; any heat soak is eliminated after a couple seconds of air flow, i.e. cranking.

[MustangMike]

I will look into that feature as I have not used it before and in the 1.4 firmware we're using it seems more complicated than the 2 settings posted here.
The idle mystery is actually an AFR mystery not a timing one. The car actually idles pretty steady except on the mysterious occasion listed in the OP where the AFR goes pig rich.
To your point though, I smoothed out the high timing cells in the low rpm column, and leaned out the ve cells under the idle cells to match in case they were affecting the idle.
After doing this I will definitely check out the advance idle feature to help keep from stalling in clutch popping and other events that might cause that.
Thanks for the info.

[Blown88GT]

What is the fuel pressure at the time of hot start, before you turn ignition key to ON?
I know you said it's steady when running.