The voltage should be 5. to .75 at closed throttle.
Remove the adjustable one and install the OEM back.
Did you set the base idle RPM? It should be 500-550 RPM.
I would start by performing the base idle procedure and reset the IAC.
The EGR valve is stuck open is also a common cause of this issue as well. I would remove the valve and clean the end as carbon can hold the valve open causing a vacuum leak and lowering the idle and stalling.
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Thursday, February 6th, 2020 AT 5:38 AM