Hold on.
"Low speed doesn't drop and I don't get high speed". That alone will no doubt MLT the unit.
Typically a DMC when found with doors open will indicate door lock issue at that floor. Most faults will close the doors. Monkeying with the low pressure adjuster will cause the car to move up, level down, move up then level down or, not close the up side properly and LOOing the motor/ valve circuit. You may have created yet another problem by goofing with the valve.
Check clutch clearance to bottom floor pick up rollers, check for door ramps on door hanger tracks causing the interlock to open up if the car/hall door drifts open. Also when on viscosity, peek through the passing jamb to see if the car is indeed moving up (it shouldn't).
And lastly, does it run up at all on auto? Broken TSL wires are common on the DMC which will allow it to run up on inspect, but just bump up but not run high or slow on automatic and going LOO or MLT. Without the FASTOOL you don't know if it's viscosity or trying to run up high, then timing out. Check the TSL wires in the switch tree.
