G&p magpul m4 only fires full auto

[Pocket Ace]

Safety - safety
Semi - full auto
Auto - full auto
Battery - either 7.4 lipo or 8.6 nunchuck battery



I been trying to figure this out for a while and I'm lost. Nothing inside the gearbox seems to be an issue. I have checked my shimming , and the turning the I think it's called sector gear ( could be wrong I'm not name proficient of the internal parts yet closest gear to trigger ) and it makes contact with the small arm that causes the break in the firing of full auto ( again I can't remember it's name ) I have replaced that little arm as well due to the original one looking fairly worn. I'm trying to find a visible broken something but nothing seems to be damaged in there. I've heard somewhere selector plate ? But what would be wrong with the plate for it to cause the issue.

Also I have a g&p 160 motor in the gun. The gun shoots very fast and I'm curious if the high speed motor has somethin to do with it.

Thanks in advance for any and all help I'm totally hands on capable of working on and in the gear box I just can't see what is causing the issue.

[Stealth]

This is a fairly common problem and could be any number of things:
* off-spec selector plate
* incompatible/worn cut-off lever
* trigger contacts too close together and causing the gun to enter into auto before the trigger trolley is in the position where it can be cut-off
* off-spec trigger

Use the diagnosis by system exclusion method to find out your root cause.