I am having difficulties adjusting a Blain EV10 valve. Here what i have observed while running on construction mode ( High speed valve not enable).

No issue in up direction - at least for now as I am still in construction mode.

In down direction.
The pressure drop from 400psi to around 200 psi and then goes up to 400psi. This causes the piston to jump. By adjusting the control #7 Down Full Speed and # 9 Down Levelling Speed,
the fault cleared. Then, on the next run in the down direction, the fault come back.

I also had an event while adjusting the down controls, 6 Down Acceleration 7 Down Full Speed 8 Down Deceleration 9 Down Levelling Speed. With the stop command enable (no down coil enable), the Cab keeps dropping for 3 feet (400psi) then does the 400psi to 200psi and then stop. I forgot what adjusted to get it stop doing that.

Any idea why this pressure change before stopping?
I did bleed the cylinder 3 times. Run the pump and moved the cylinder upwards. Open bleed valve until oil squeeze out. Could there still be air inside?
I run the pump while opening the emergency valve (I once was told that would clear any dirt)
In this job, we are changing the Pump and Controller. Cylinder and Line rupture valve still the original.