Spirit rs speed control problem

[shi555]

I am using HOBBYWING platinum hv160A v4, which comes with an rpm plug. After wiring it correctly, turning on the constant speed and setting the correct gear ratio, the test found that the rmp jumps up and down in a large range (7xxx, 8xxx and then jumps to 0). I tried to change the gear ratio and magnetic pole. , but its current rpm is always higher than the target value. This is obviously incorrect, what should I do?

[ZeXx86]

Hello,

is the yellow RPM wire connected at the PIT pin?
This is in the middle of the port.

[shi555]

Hello,

is the yellow RPM wire connected at the PIT pin?
This is in the middle of the port.

Yes just plug in the rpm plug individually to the middle position. No telemetry callback connected

[shi555]

Hello,

is the yellow RPM wire connected at the PIT pin?
This is in the middle of the port.

yes only it to pit pin