If it is connected to both that you can not operate on resistance - you will need voltage levels (because other gauge power supply it and translate resistance to voltage and translation depends on internal circuit in other gauge - you do not know this circuit).
It such case it should be connected to AdcX.
If you will connect it only to UTCOMP that resistance is enough and it should be connected to AdcVccX ports.
I calibrated temperature sensor based on resistance - when sensor is connected ONLY to AdcVccX in utcomp
(and disconnected from other gauge), than R25 = 2037, Beta = 4251 and error <1C.
For pressure sensor it should be first translated to bar:
250 ohms = 0psi = 0 bar
158 ohms = 25psi = 1,72 bar
111 ohms = 50psi = 3,45 bar
75 ohms = 75psi = 5,17 bar
43 ohm = 100 psi = 6,89 bar
and it seems that you have wrong measurements because it is not linear in whole range (and it should be):
I can linearize in range of 2-7 bar but error will be about 0,2-0,3bar:
in such case a = -10,44, b = 9,13
and again - sensor should be connected only to AdcVccX in utcomp
(and disconnected from other devices)
If you would like to use the sensor on multiple gauges, than please share real voltage tables.
I'll help you to scale it