Make sure there's plenty of air coming out of your car vents on HIGH fan. Also, charge your system when the interior fan is on high. If the air is restricted, that will freeze the evaporator. That will give you a low suction reading. Low refrigerant will also do the same.
If the TXV has a sensing bulb attached to the suction line, remove it. Look at your pressures and see how your suction pressure deflects. Should go up. Now put the sensing bulb in ice water or rag with ice). The suction pressure should go down. If it deflects, the TXV is working 90% of the time. If you have a TXV block with the sensing bulb on top. Ran the AC for a couple of minutes then shut the engine off. Both gauges should equalize within 2 minutes. If it takes much longer than that or if it doesn't equalize. 20:1 it's the TXV.
A properly running unit should have a suction pressure between 25 and 40 psi and head pressure around 150. It's all according how hot the ambient temperature is outside and in the vehicle.. hard to diagnose when not there. Good luck.