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Unstable idle when sudden off throttle

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New to tuning so don’t burn me.

I switched to haltech platinum pro for my EVO 9 then I took it to the same tuner when I had the stock ECU. Now before I take back to him. I want to see if I can fix it first.

If the A/C is off, the idle is stable on or off throttle, no issues. Once I turn on the a/c, during idle, its stable. However once I started driving and I go on and off throttle, the engine drops to almost stalling the car. Sometimes, when I have the a/c and I’m backing out of the parking lot and the power steering kicks in, it stalls the car.

I increased the idle 200 rpm but to prevent from stalling the car but that’s just a band-aid to the current issue.

It’s a new engine from factory (zero miles) and I just put in 3000 miles into it. New haltech ECU. If I swap the stock ECU there are no issues. I also don’t think it’s the idle control valve since it is stable if the a/c is not on.

I attached a video of me driving with traffic and when I go neutral and off throttle, the idle drops before it stabilizes.

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hello i would be thinkin it is the base step setting in the idle set up which is the base open or step number used to hold the idle just above the desired rpm and then the closed loop control will bring the idle to the desired rpm, if this step is to low the idle will under shoot and then ramp up as the closed loop works out where it is

take a look at this screen on your ecu

this is the base setting %

if it does it just when turning or load is added like fans etc there are other settings in the map for that '

Am I on the right map? if not walk me through it because yours might be named differently or i do not have that feature.

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