When you start a fuel injected engine cold the idle should go up to 1,600 then drop to about 1,200rpms
It should then slowly drop to about 750rpms diuring 8 minute warm up.
That's the computer operating the IAC valve.
Computer opens IAC Valve all the way on startup, thats the 1,600
It then checks the engine temp using ECT sensor, if cold that's the 1,200
As Engine warms up per ECT sensor computer will lower the idle until "warm idle" target is set.
So try starting engine cold, DO NOT touch the gas pedal.
If engine won't start you have other issues
I would guess a vacuum leak since that is a common issue.
Second would be EGR valve stuck open, EGR valve should only be open AFTER warm up, and then only when engine is under a load, accelerating or going uphill.
Vacuum leak and EGR issue would effect idle the most, engine could seem to run OK while at higher RPMs