Idle issue when the car is hot

You need to either find a new tuner or learn how to do it yourself.
Idle (and basic engine operation) comes down to air, fuel, and spark. If one or more of these 3 isn't where it needs to be, you'll have problems....and unless you have some magical flywheel, it's not the culprit.
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Just figured this out today, but your RAF does need to be close before that will matter.
If the car is idling fine, say @ 180~190*F or so, turn on both fans via the VCM controls, if it stumbles and almost kills like it does the way you describe it, that could be it.
To alleviate it you will want to bump up the "Cooling Fan Airflow" for "Fan 1 & 2"
I bumped mine up from .2 to .45
It doesn't dip nearly as far when they kick on now.
Just stumbled on this thread and reminded me of what I just tackled today.
May or may not be your problem.





