Santa Fe 2002 2.4L P0171

Hello maybe someone will help me and point next step for me .
So I have code P0171 and data from car:

Engine load: 50.20%
Engine RPM: 2359
Speed: 94 km/h
Long term fuel % trim - Bank 1 :12.50%
Short term fuel % trim - Bank 1 :12.50%
Engine coolant temperature: 85.00 C
Fuel system status: Closed loop: using O2 for fuel mix.

I have new MAF (was changed few month ago, and now checked readings still good 2.7g),
have changed O2 sensor just to try, and both gives the same data (will see in attachmen),
Spark wires with coils was changed to new few month ago because was bad.

when driving sometimes engine stalls when accelerator fully depressed and without gear (in neutral)

Should i seek for vacuum leak, or something else?

is your fuel trim higher at idle? if so that usually points to a vacuum leak. if it gets worse as you rev up it could be low fuel pressure.

There is an attachment with trims rpm and o2 data.

But at idle ltft about 10% and on rpm rise up to 12.50%

I forgot to mention my car with lpg, but same happens with petrol and lpg.

What you describe and the symptoms tells me that it's should be either a bad MAF or fuel pressure. Check the O2 signal when accelerating if it goes lean then that's your direction.